They wrote that the claims and policy changes in the memo from Vinay Prasad, the head of the FDA’s Center for Biologics Evaluation and Research, pose “a threat to evidence-based vaccine policy and public health security” and break sharply from long-standing scientific norms.

What is unfolding inside the FDA is not a narrow dispute over covid vaccines. It is an attempt, according to critics and vaccine scientists, to rewrite the rules governing the entire U.S. vaccine system — how risks are weighed, how benefits are proved, and how quickly lifesaving shots reach the public. Former agency leaders warn that if these changes take hold, the consequences could be lasting: fewer vaccines, slower updates, weakened public trust, and more preventable outbreaks.

Prasad made clear he sees the moment as corrective. “Never again will the US FDA commissioner have to himself find deaths in children for staff to identify it,” he wrote, telling employees the agency’s mission, and its “worldview,” would change.

Prasad’s email reopened old arguments about covid vaccines, using what is generally considered weak and misleading science in the peer-reviewed research community. He claimed that FDA staff had found “at least 10” deaths in children that happened “after and because of” covid vaccination, using reports from the Vaccine Adverse Event Reporting System.

The VAERS system is notoriously crowdsourced, meaning anyone can contribute, and scientists say it serves only as a clearinghouse for reports. For example, a person could file a report saying that after getting a flu shot, their hair turned purple. Though that report would remain in the database until it was reviewed, it cannot prove the cause of medical events. But Prasad argued that the true number of deaths was likely higher because many cases go unreported.

On Substack, Inside Medicine reported Dec. 11 that Prasad used incomplete information and that a Dec. 5 internal FDA memo set the pediatric death toll from covid shots somewhere between zero and seven. Department of Health and Human Services spokesperson Emily Hilliard wrote, “The FDA’s investigation into deaths caused by Covid vaccines is still ongoing and there’s no final count yet of those deaths.”

Prasad also accused the FDA and the Centers for Disease Control and Prevention of downplaying the risk of heart inflammation, called myocarditis, in young men; criticized the agency for approving shots for teenagers; and suggested that school and workplace vaccine mandates may have “harmed more children than we saved,” adding that “we do not know if we saved lives on balance.”

By comparison, more than 2,100 American children died of covid itself since the pandemic began, the CDC reported.

Based on his erroneous and misleading claims about covid vaccines, Prasad proposed a major overhaul of how vaccines are approved. He said the FDA should stop relying on immune markers to establish the efficacy of shots, such as antibody levels, and instead require large placebo-controlled randomized trials that track hospitalizations and deaths before approving most new vaccines.

Many immunologists and vaccine experts say it’s unethical to test vaccines known to be effective against disease with a control group that would receive a placebo, exposing them to infection.

“There is a rock-solid principle in bioethics that it is unethical to test any drug or vaccine against a placebo if it is known to be safe and effective. The reason is that such placebo-controlled trials would effectively deny patients access to a vaccine that could prevent a dangerous infectious disease,” said Lawrence Gostin, a professor of global health law at Georgetown University.

Prasad called the current flu vaccine system an “evidence-based catastrophe,” questioned the approval of vaccines for pregnant women based on immune response alone, and raised concerns about giving multiple vaccines at once. He told staff to rewrite FDA guidelines to match his new “worldview” and said anyone who disagreed with his “core principles” should resign.

The former FDA leaders expressed alarm in the NEJM article. They said Prasad is exploiting public frustration over the federal response to covid to spark doubt about the entire childhood vaccine system, which could undo decades of success in protecting children from deadly diseases.

“This is really different. And it’s really dangerous. And people will be hurt, particularly by the vaccine decisions,” former FDA commissioner Robert Califf said in an interview. He also warned that Prasad’s proposed policies — which he noted echo positions on vaccines held by Health and Human Services Secretary Robert F. Kennedy Jr., a longtime anti-vaccine activist — could shake the entire vaccine market.

“The goal of RFK seems to be to make it impossible for vaccines to be available in the U.S.,” he said. If the proposals advance, he added, “it won’t be a viable business.”

Hilliard pushed back sharply on those concerns, writing: “The American people deserve evidence-based science. Prasad’s email lays out a philosophical framework that points us toward that higher standard. We will soon release documents laying out that framework and data confirming how the COVID vaccine resulted in children’s deaths that previous leadership failed to properly investigate.”

For generations, the childhood vaccine program has depended on clear rules, strong safety systems, and public trust. Experts say Prasad’s ideas, based on claims they argue are not supported by real evidence, could make it much harder to test, approve, and deliver vaccines to families.

Fueling Parental Doubt

Prasad’s memo indicates he considers VAERS reports as proof that vaccines caused children’s deaths. The system, though, is designed to be only an “early warning system” for potential safety issues with vaccines that can be investigated further.

“VAERS signals should never be taken as proof of true vaccine risks without careful, confirmatory studies,” said Katherine Yih, an epidemiologist and longtime investigator with the Vaccine Safety Datalink, a CDC program.

Doing so, scientists say, directly feeds public fear at a time when many parents are already unsure whom to trust.

“Causation requires converging evidence, not just one report or coincidence,” said Robert Hopkins, medical director of the National Foundation for Infectious Diseases.

Prasad’s framework, however, treats uncertainty as a reason to halt development entirely.

Experts fear this doubt won’t stay limited to covid vaccines. Once parents start to question the FDA’s honesty, they may begin doubting long-standing vaccines for measles, polio, or whooping cough — shots that have protected children for decades.

“Science must be transparent,” Gostin said. If families believe the FDA is misusing data or silencing experts, confidence in the entire vaccine system can collapse, he said. “There’s a public narrative that people have lost trust in science, but that’s not true. The vast majority want the FDA to make decisions based on the best scientific evidence. Once they believe that the agency is marginalizing scientists and cherry-picking evidence, their trust will plummet.”

Delicate Vaccine Pipeline

Prasad’s new framework will likely make it far harder for companies to produce or update vaccines. The 12 former FDA commissioners warned that requiring clinical trials for all new or updated shots would slow vaccine improvements and leave people unprotected. His plan, they wrote, “would impede the ability to update vaccines in a timely fashion, especially for respiratory viruses.”

For fast-changing viruses like flu and covid, this could be disastrous. There’s simply not enough time to run full clinical trials every time a virus mutates.

There are also major business effects. Vaccine development is costly, and companies may decide the U.S. is no longer worth the risk. If companies slow down or leave the market, families could face shortages, fewer innovations, and fewer protections for their kids.

‘Checks and Balances’

Science depends on open and public debate. Prasad’s memo warned his employees against it. In addition to demanding that FDA staff members who disagree with him resign, he said their disputes should stay private and called leaks “unethical” and “illegal.”

Susan Ellenberg, a former director of the FDA’s Office of Biostatistics and Epidemiology, warned that Prasad risks destroying the process that makes science credible. “If disagreement is treated as disloyalty, you lose the only mechanism that keeps science honest,” she said.

Without strong internal debate, safety reviews become weaker. “You lose the checks and balances that make vaccine safety science credible,” said Kathryn Edwards, a pediatric infectious disease specialist at Vanderbilt University Medical Center who served on the Clinical Immunization Safety Assessment Network during the covid pandemic.

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“Tenía 18 años, estaba sana, en la universidad”, contó. “Y de repente tenía una enfermedad crónica de la que ni siquiera sabía”.

Wang nació en Florida en 1975, antes de que se aplicara de manera rutinaria la vacuna contra la hepatitis B a los recién nacidos.

Durante años, supuso que se había contagiado por su madre, pero más adelante descubrió que sus padres no tenían el virus. “Resulta que probablemente fueron mis abuelos, quienes me cuidaron después de nacer, quienes me lo transmitieron”, dijo.

“Así de fácil se contagia este virus: no por algún factor de riesgo exótico, sino en el entorno familiar”, agregó.

Hoy, Wang es directora médica de los programas de hepatitis viral en RWJBarnabas Health en Nueva Jersey. Su historia está en el centro de un punto de inflexión histórico en la salud pública.

El 5 de diciembre, el Comité Asesor sobre Prácticas de Vacunación (ACIP, por sus siglas en inglés) de los Centros para el Control y Prevención de Enfermedades (CDC, por sus siglas en inglés) votó para poner fin a la recomendación universal de aplicar la vacuna contra la hepatitis B a los recién nacidos, adoptando en su lugar una política basada en decisiones individuales.

Con este nuevo enfoque, solo los bebés cuyas madres den positivo para la hepatitis B recibirán automáticamente una dosis de la vacuna y anticuerpos contra el virus poco después de nacer. En los demás casos, si los padres deciden vacunar, la primera dosis se puede postergar hasta los 2 meses de edad.

Todos los miembros del comité fueron nombrados por el secretario de Salud y Servicios Humanos, Robert F. Kennedy Jr., un conocido activista antivacunas.

En una votación de 8-3, el panel decidió que, dado que la mayoría de las mujeres embarazadas actualmente se someten a pruebas para detectar hepatitis B, la aplicación de la vacuna al nacer debería reservarse para los bebés cuyas madres den positivo.

Los miembros del panel presentaron el cambio como una forma de reducir intervenciones innecesarias, alinear la vacunación con los resultados de las pruebas y darles a los padres más control sobre el momento de la aplicación.

Quienes apoyaron la decisión la describieron como una medida que promueve la elección de los padres, más que como un reflejo de un cambio en la epidemiología.

Pero para muchos profesionales clínicos y epidemiólogos, este cambio representa un retroceso peligroso que podría revertir tres décadas de avances hacia la eliminación de una enfermedad que aún infecta a unos 2,4 millones de personas en el país y que provoca decenas de miles de muertes cada año.

Perciben ecos de los años 80, cuando un enfoque basado en factores de riesgo dejó a generaciones sin protección, y temen que el país esté por repetir ese error.

Además, la decisión del panel sobre la hepatitis podría ser uno de varios cambios que podrían desestabilizar el calendario nacional de vacunación infantil, una piedra angular de la salud pública.

“No están tratando de cambiar una sola vacuna”, dijo Angela Rasmussen, viróloga y editora de la revista científica Vaccine. “Están tratando de desmantelar la manera en que se establece la política de vacunación”.

La vocera del Departamento de Salud y Servicios Humanos, Emily Hilliard, respondió: “El ACIP revisa toda la evidencia presentada y emite recomendaciones basadas en pruebas y buen juicio, con el fin de proteger de la mejor manera posible a los niños en Estados Unidos”.

Los autores de una nueva revisión independiente del Vaccine Integrity Project, que evaluó más de 400 estudios e informes, advirtieron en un comentario público que retrasar la dosis al nacer “reduciría la protección de los bebés y aumentaría el riesgo de infecciones evitables por el virus de la hepatitis B (VHB), lesionando décadas de avances” hacia su eliminación.

La revisión fue dirigida por investigadores del Centro de Investigación y Políticas de Enfermedades Infecciosas de la Universidad de Minnesota, que creó el Vaccine Integrity Project en respuesta a lo que considera acciones del gobierno de Trump que “pusieron en riesgo el panorama federal de vacunación”.

La revisión fue evaluada por expertos externos.

“Luchamos mucho para lograr esa dosis universal al nacer”, dijo Wang. “Sabemos lo que pasa cuando uno espera”.

El debate gira en torno a algunas preguntas clave: si las pruebas son lo suficientemente confiables como para reemplazar las protecciones universales, qué tan contagiosa es realmente la hepatitis B, por qué fracasaron las estrategias del pasado y qué significan los cambios internos en los CDC para la política de vacunación en general.

Los límites de las pruebas

Las pruebas de hepatitis B están en el centro de la nueva recomendación del ACIP, pero incluso los CDC reconocen que las pruebas por sí solas no garantizan protección.

Las mujeres embarazadas pueden dar negativo si contraen el virus al final del embarazo o durante el “período de ventana”, antes de que los antígenos de la hepatitis B sean detectables. También hay falsos negativos. Ningún sistema de pruebas, por bien diseñado que esté, puede detectar todas las infecciones.

Por eso se creó la vacunación universal.

Si se desconoce el estado de la madre en el momento del parto, los hospitales deben aplicar la vacuna al bebé dentro de las 12 horas y agregar anticuerpos contra la hepatitis B en el caso de los bebés prematuros o si la madre da positivo más tarde. Pero en la práctica clínica real, estas medidas de seguridad suelen fallar. Los resultados tardan en llegar. Algunas enfermeras omiten o interpretan mal los análisis. Las farmacias retrasan las entregas. Se pierde la documentación.

“Cada paso adicional aumenta la posibilidad de que algo se pase por alto”, dijo Wang. “Retrasar la vacuna simplemente agrega otro paso”.

La votación del ACIP demuestra cómo se está cuestionando esa lógica.

Algunos miembros del comité sugirieron eliminar la tercera dosis de la vacuna si los niveles de anticuerpos se ven elevados después de la segunda.

Pero Brian McMahon, especialista en enfermedades hepáticas que ha tratado hepatitis B durante décadas, dijo al panel que los datos no respaldan esa idea. “Solo entre el 20% y el 30% de los bebés presentan niveles adecuados de anticuerpos después de la primera dosis”, señaló.

“Se necesitan dos dosis para lograr una protección alta”, dijo, y agregó que la tercera proporciona una respuesta más fuerte y duradera.

McMahon dijo que el mensaje general del comité parecía estar orientado a “desalentar la dosis al nacer”.

“Están poniendo cada vez más trabas”, dijo McMahon.

En una segunda votación, el ACIP también alentó a los padres y profesionales a solicitar pruebas serológicas después de la segunda o tercera dosis —análisis de sangre que miden los niveles de anticuerpos protectores—. Según el comité, estas pruebas deberían estar cubiertas por el seguro médico.

Más contagiosa que el VIH o la hepatitis C

El virus de la hepatitis B puede sobrevivir hasta una semana en cepillos de dientes, rasuradoras y superficies del hogar. Se transmite no solo de madre a hijo, sino también mediante el contacto familiar cotidiano: objetos compartidos, heridas abiertas, pequeñas exposiciones a sangre. En los años 80, investigadores descubrieron que cerca de la mitad de las infecciones en niños estadounidenses no provenían de la madre, sino de otros miembros del hogar.

Por eso, los departamentos de salud estatales siguen insistiendo en que se vacune a todos los recién nacidos dentro de las primeras 24 horas, sin importar el estado de salud de la madre.

“Retrasar la vacunación implica perder un período clave de posible exposición”, advirtió una guía de Nueva York este año. La vacuna, señaló, tiene una efectividad de entre 80% y 100% cuando se aplica a tiempo.

El informe del Vaccine Integrity Project destaca lo que está en juego. Desde que se introdujo la dosis universal al nacer en 1991, las infecciones pediátricas por hepatitis B en Estados Unidos han disminuido más del 99%.

Un análisis de los CDC de 2024 estimó que el calendario actual ha prevenido más de 6 millones de infecciones por hepatitis B y cerca de 1 millón de hospitalizaciones.

Los beneficios duran toda la vida. Los bebés vacunados al nacer están protegidos no solo de la hepatitis B, sino también de la insuficiencia hepática y el cáncer que puede causar décadas más tarde.

Sin embargo, como la enfermedad avanza lentamente, las consecuencias de los cambios en la política podrían tardar 20 o 30 años en manifestarse.

Trieu Pham, médico de California, no necesita imaginar esas consecuencias. Nacido en Vietnam en 1976, probablemente contrajo el virus al nacer. “Si la vacuna hubiera existido entonces, no habría pasado por todo lo que pasé”, dijo. Le diagnosticaron hepatitis B en sus 20, desarrolló cirrosis a los 40. A los 47, tosía sangre por la ruptura de venas esofágicas. Finalmente, necesitó un trasplante de hígado para sobrevivir.

“Uno vive con un cansancio constante y con miedo”, contó. “Y lo más triste es que era prevenible”.

Sus tres hijos, vacunados a las pocas horas de nacer, no tienen hepatitis B. “Esa es la diferencia que puede hacer un solo día”, dijo Pham.

Una lección aprendida

En 1982, el ACIP recomendó la nueva vacuna contra la hepatitis B solo para adultos con alto riesgo: trabajadores de salud, personas que usan drogas inyectables y hombres que tienen relaciones sexuales con hombres.

Pero a finales de los años 80, quedó claro que la vacunación basada en factores de riesgo no lograba contener la transmisión. Muchos adultos recién infectados no pertenecían a los grupos definidos como de alto riesgo. Identificarlos resultó imperfecto, estigmatizante y, al final, ineficaz.

Mientras tanto, los bebés infectados durante o poco después del parto tenían un 90% de probabilidad de desarrollar infección crónica, en comparación con menos del 5% en adultos. Sin embargo, las autoridades de salud pública repitieron la misma estrategia focalizada, esta vez con recién nacidos.

En 1988, los CDC recomendaron pruebas prenatales universales y vincularon la vacunación del bebé al resultado de la madre, basando de nuevo la protección en un marcador de riesgo en lugar de vacunar a todos los bebés.

Como antes, la estrategia fracasó.

Muchas madres infectadas no fueron identificadas correctamente. Algunas no se hicieron la prueba, otras la hicieron demasiado temprano, y hubo casos en que los resultados se interpretaron mal o nunca se comunicaron. Demasiados bebés quedaron sin protección, una prueba más de que el enfoque dirigido no era confiable.

En 1991, los CDC emitieron una guía histórica que recomendaba vacunar a todos los recién nacidos, sin importar el estado de infección de la madre, y aplicar dos dosis adicionales durante la infancia.

Para 2005, la política estaba completamente integrada en el calendario de vacunación rutinaria y fue ratificada nuevamente en 2018.

Esta evolución se basó en datos que demostraban que una estrategia universal era más efectiva para prevenir infecciones que una basada en riesgos.

Una cuestión de confianza

La nueva política sobre la hepatitis B de los CDC parte del supuesto de que trasladar la decisión a los padres fortalecerá la confianza en el sistema de vacunación. Quienes la apoyan la presentan como un cambio que empodera, una manera de darles más control a las familias.

En 1999, cuando se recomendó por última vez postergar la primera dosis de la vacuna contra la hepatitis B en bebés cuyas madres no estaban infectadas, también disminuyeron las tasas de vacunación entre los bebés de madres que sí lo estaban.

“Las políticas de consentimiento suenan centradas en el paciente, pero en la práctica no son equitativas. Dejan fuera justamente a las familias que más necesitan protección”, dijo Wang. Es decir, a aquellas que probablemente no acceden a atención prenatal ni a pruebas, que tienen infecciones no detectadas o adquiridas después de las pruebas, así como a bebés que pueden estar expuestos a cuidadores u otros miembros del hogar.

Con frecuencia, se trata de familias inmigrantes, incluyendo comunidades asiáticas y de las islas del Pacífico, donde la hepatitis B sigue siendo endémica. “Ya diagnosticamos y tratamos poco a estas poblaciones”, dijo Wang. “Este cambio solo profundizaría esa brecha”.

Estados Unidos es ahora el único país que ha abandonado la recomendación de una dosis universal al nacer contra la hepatitis B. Aunque tomará décadas reunir datos sobre los resultados, algunos investigadores predicen que retrasar la primera dosis hasta los 2 meses podría resultar en más de 1.400 infecciones evitables y unos 300 casos de cáncer de hígado por año.

“No elegimos lo que heredamos”, dijo Wang. “Pero sí podemos elegir lo que dejamos a las próximas generaciones”.

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“I was 18, healthy, in college,” she said. “And suddenly I had a chronic illness I didn’t even know about.”

Born in Florida in 1975, Wang grew up before the hepatitis B vaccine was routinely given to newborns. For years, she assumed she had been infected by her mother, only to discover later that both her parents were negative. “It turns out my grandparents, who cared for me after birth, probably passed it to me,” she said. “That’s how easy this virus spreads — not from some exotic risk factor, just family.”

Today, Wang is the medical director for viral hepatitis programs at RWJBarnabas Health in New Jersey. Her story now sits at the center of a historic turning point in public health.

On Dec. 5, the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices voted to end the universal U.S. recommendation for the newborn dose of the hepatitis B vaccine, instead adopting a policy urging individual-based decision-making.

Under the new approach, only infants born to mothers who test positive for hepatitis B will automatically receive a dose of the vaccine and hepatitis B antibodies shortly after birth. For everyone else, if the parents choose to vaccinate, the birth dose can be delayed until 2 months of age.

All the committee members were appointed by Health and Human Services Secretary Robert F. Kennedy Jr., a longtime anti-vaccine activist. In an 8-to-3 vote, the panel decided that since most pregnant women now receive hepatitis B testing, administering the vaccine at birth should be reserved for infants whose mothers test positive. They framed the shift as a way to reduce interventions deemed unnecessary, align vaccination with test results, and give parents more control over timing. Supporters of the decision described it as a move toward parental choice rather than a reflection of changing epidemiology.

But to many clinicians and epidemiologists, the change represents a dangerous rollback that could reverse three decades of progress toward eliminating a disease that still infects as many as 2.4 million Americans and kills tens of thousands each year. They see echoes of the 1980s, when risk-based vaccination left entire generations unprotected, and worry the country is about to repeat that mistake.

Moreover, the panel’s move on hepatitis B — in the face of overwhelming data that shows the birth dose is effective and safe — portends further upheaval for the nation’s childhood vaccine schedule, a cornerstone of public health.

“They’re not just trying to change one vaccine,” said Angela Rasmussen, a virologist and an editor of the scientific journal Vaccine. “They’re trying to dismantle how vaccine policy is made.” 

Department of Health and Human Services spokesperson Emily Hilliard responded: “ACIP reviews all evidence presented and issues recommendations based on evidence and sound judgment to best protect America’s children.”

The authors of a new independent review by the Vaccine Integrity Project, which evaluated more than 400 studies and reports, warned in a public comment that delaying the birth dose “would reduce protection for infants and increase the risk of avoidable HBV infections, undermining decades of progress” toward eliminating the hepatitis B virus. The review was led by researchers at the University of Minnesota’s Center for Infectious Disease Research and Policy, which created the Vaccine Integrity Project in response to what it regards as Trump administration actions that “put the federal vaccine landscape at risk,” and it was vetted by outside experts.

“We fought hard for that universal birth dose because targeted approaches missed too many babies,” Wang said. “We know what happens when you wait.”

What’s unfolding now is not just a technical policy update but a fundamental test of the systems meant to protect the most vulnerable. The debate turns on a few critical questions — whether testing is reliable enough to replace universal safeguards, how infectious hepatitis B truly is, why past strategies failed, and what the CDC’s internal shake-ups mean for vaccine policy writ large.

The Limits of Testing

Hepatitis B testing sits at the center of the new ACIP recommendation, but even the CDC acknowledges that testing alone can’t guarantee protection. Pregnant women may test negative if the virus was acquired late in pregnancy or during the “window period,” before hepatitis B surface antigens become detectable. False negatives happen. No testing system, no matter how well designed, can catch every infection. That’s why universal vaccination was created in the first place.

If a mother’s status is unknown at delivery, hospitals are supposed to give the newborn a hepatitis B vaccine within 12 hours, adding hepatitis B antibodies for premature infants or if the mother later tests positive. But in real clinical settings, these safeguards routinely break down. Results take time. Nurses miss or misread labs. Pharmacies delay deliveries. Documentation gets lost.

“Every step you add increases the chance that something falls through the cracks,” Wang said. “Delaying the vaccine just adds another.”

ACIP’s vote shows how that logic is being challenged.

Some committee members suggested dropping the third hepatitis B shot if antibody levels look high after the second. 

But Brian McMahon, a liver disease specialist who has spent decades treating hepatitis B, told the panelists that the data doesn’t support that idea. “Only maybe 20% to 30%” of infants have an adequate antibody level after the first dose, he said.

“You need two doses to really reach a high level of protection,” he said, with the third shot giving a stronger, longer-lasting response.

He said the overall message coming from the committee seemed designed to “discourage the birth dose.”

“They’re making it more and more difficult,” McMahon said.

In a second vote, ACIP also encouraged parents and clinicians to order post-vaccine serology tests — blood tests that measure protective antibody levels — after the second or third dose. The tests, ACIP said, should be covered by insurance.

More Infectious Than HIV or Hepatitis C

Hepatitis B can survive on toothbrushes, razors, and household surfaces for a week. It spreads not just from mother to child but also through ordinary family contact: shared items, open sores, small blood exposures. In the 1980s, researchers found that about half of infections in American children came not from mothers but from other household members.

That’s why state health departments continue to insist that every newborn be vaccinated within 24 hours of delivery, regardless of maternal status. “Delaying vaccination misses a crucial period of potential exposure,” a New York advisory warned this year. The vaccine, it noted, is 80% to 100% effective when given on time.

The Vaccine Integrity Project report underscores the stakes. Since the universal birth dose was introduced in 1991, pediatric hepatitis B infections in the U.S. have dropped by more than 99%. A 2024 CDC analysis estimated that the current schedule has prevented more than 6 million hepatitis B infections and nearly 1 million hospitalizations.

The benefits are lifelong. Infants vaccinated at birth are shielded not just from hepatitis B but also from the liver failure and cancer it can cause decades later. Yet because the disease unfolds slowly, the consequences of policy shifts may not surface for 20 or 30 years.

Trieu Pham, a California physician, doesn’t need to imagine those consequences. Born in Vietnam in 1976, he probably contracted the virus at birth. “If the vaccine had existed then, I wouldn’t have gone through what I did,” he said. Diagnosed in his 20s, he developed cirrhosis by 40. At 47, he was coughing blood from ruptured esophageal veins. Eventually, he required a liver transplant to survive.

“You live with this constant fatigue and fear,” he said. “And the saddest part is it was preventable.”

His three children, all vaccinated within hours of birth, are free of hepatitis B. “That’s the difference a day can make,” Pham said.

A Lesson Already Learned

In 1982, ACIP recommended the new hepatitis B vaccine only for adults at high risk: health care workers, injection drug users, and men who have sex with men. But by the late 1980s, it was clear that risk-based vaccination couldn’t contain transmission. Many newly infected adults didn’t fit any defined risk group. Identifying high-risk people proved imperfect, stigmatizing, and ultimately ineffective.

Meanwhile, infants infected during or shortly after birth had a 90% chance of developing chronic infection, compared with less than 5% in adults. Yet public health officials repeated the same targeted strategy, this time with newborns. In 1988, the CDC recommended universal prenatal screening and linked an infant’s vaccination to the mother’s test result, again basing protection on a risk marker instead of vaccinating all infants.

As before, it failed. Many infected mothers weren’t correctly identified. Some were never tested, some were tested too early, and others had results that were misread or never communicated. Too many infants slipped through the cracks, proof that another targeted approach couldn’t reliably protect them.

In 1991, the CDC issued its landmark guidance recommending that all infants, regardless of their mother’s infection status, receive a hepatitis B vaccine at birth, followed by two additional doses in infancy. By 2005, the policy was fully embedded in the routine immunization schedule, then reaffirmed in 2018. This evolution was based on data showing that a universal strategy, rather than a targeted one, was the most effective in preventing infections.

A Matter of Trust

The CDC’s new hepatitis B policy rests on the premise that moving the decision to parents will strengthen trust in the vaccine system. Supporters frame it as an empowerment shift — a way to give families more control.

In 1999, when it was last recommended to postpone the first dose of hepatitis B vaccine for infants born to uninfected mothers, vaccination rates also dropped among infants born to those who were infected.

“Opt-in policies sound patient-centered,” Wang said, “but in practice they’re inequitable. They leave behind the very families who need protection most” — the ones most likely to miss prenatal care and testing, have infections that go undetected or arise after testing, or slip through gaps in hospital care, as well as infants who can be exposed and infected by other caregivers and household members.

Those are often immigrant families, including from Asian and Pacific Islander communities in which hepatitis B remains endemic. “We already underdiagnose and undertreat these populations,” Wang said. “This change would deepen that gap.”

The United States is now the only country to abandon a universal hepatitis B birth dose recommendation. Though it will take decades to gather outcomes data, some researchers predict that delaying the first dose of hepatitis B vaccine to 2 months of age could result in over 1,400 preventable infections and about 300 cases of liver cancer per year.

“We don’t get to choose what we inherit,” Wang said. “But we do get to choose what we pass on.”

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Según entrevistas con funcionarios de salud estatales y federales, los brotes son impulsados por la caída en las tasas de vacunación, la disminución de la inmunidad y los retrasos en los sistemas de vigilancia de salud pública. Los bebés que aún no han recibido el esquema completo de vacunación son los que están en mayor riesgo.

“Los casos de tos ferina aumentan de forma cíclica debido a la inmunidad decreciente, pero el tamaño del brote y el riesgo de desenlaces graves en niños que no pueden vacunarse pueden reducirse si hay una alta cobertura y buena comunicación con las personas en riesgo”, dijo Demetre Daskalakis, ex director del programa de inmunización de los Centros para el Control y Prevención de Enfermedades (CDC), quien renunció en agosto.

Antes de que estuviera disponible la primera vacuna contra la tos convulsa, a principios del siglo XX, esta enfermedad era una de las más comunes en la infancia y una causa importante de muerte infantil en Estados Unidos.

Hoy en día, los niños reciben una serie de vacunas DTaP (versión de dosis completa) a partir de los 2 meses, y los adolescentes y adultos reciben un refuerzo Tdap (versión de menor dosis) cada 10 años. (Ambas vacunas también protegen contra la difteria y el tétanos).

Hasta hace poco, 8 de cada 10 niños pequeños habían recibido cuatro dosis de la vacuna DTaP para cuando cumplían 2 años, y los casos se mantenían bajo control. Pero la cobertura ha disminuido desde la pandemia de covid y el aumento de las exenciones por motivos no médicos en varios estados ha ampliado las brechas de inmunidad, que ocurren cuando la proporción de personas inmunes cae por debajo del nivel necesario para frenar la propagación.

Texas registró 1.928 casos de tos convulsa en 2024. Para octubre de 2025, el estado ya superaba los 3.500. A nivel nacional, las cifras son igual de alarmantes: en los primeros tres meses de 2025, se reportaron 6.600 casos, cuatro veces más que el ritmo del año pasado y 25 veces más que en 2023. Varios estados están reportando sus cifras más altas en una década, y los brotes, desde Louisiana hasta Dakota del Sur y Idaho, dejan claro que este aumento no es regional. Es generalizado.

Factores clave detrás del aumento

Recientemente, legisladores de Texas aprobaron una ley que facilita a los padres solicitar exenciones por motivos no médicos a los requisitos de vacunación escolar, permitiendo que bajen los formularios de internet. Estos formularios ahora se envían directamente a las escuelas, no a los departamentos de salud, lo que dificulta su seguimiento.

Phil Huang, director del Departamento de Salud y Servicios Humanos del condado de Dallas, dijo que aún no se conoce el impacto completo de esta nueva norma, ya que comenzó a aplicarse este año escolar, pero espera que las tasas de vacunación escolar sigan bajando.

Ya ha notado una baja considerable en las vacunaciones. Normalmente, durante la temporada de regreso a clases, “toda nuestra área de atención en la planta baja estaba llena”, dijo. “Este año no fue así”.

Huang cree que el temor a las medidas migratorias podría estar haciendo que algunas familias, en particular las hispanas, eviten vacunarse. El condado de Dallas tiene una población hispana de alrededor del 40%. “Creemos que muchos se ven disuadidos por la actividad de ICE”, señaló, refiriéndose al Servicio de Inmigración y Control de Aduanas.

Hay más complicaciones: estas vacunas protegen contra formas graves de la enfermedad, pero su protección contra la infección disminuye con el tiempo, como ocurre con las vacunas contra covid y la gripe.

En los años 90, Estados Unidos cambió de vacunas contra la tos convulsa, de células completas a vacunas “acelulares”, que causan menos efectos secundarios, pero cuya protección dura menos tiempo. Dado que quienes son adultos hoy en día recibieron la vacuna acelular durante la infancia, han perdido inmunidad con el tiempo y podrían contagiar sin saberlo a los bebés.

Los bebés tienen más riesgo

La tos ferina es especialmente peligrosa para bebés menores de un año. Algunos dejan de respirar durante los ataques de tos. Muchos necesitan hospitalización; de ellos, 1 de cada 5 desarrolla neumonía y cerca del 1% muere.

Debido a este alto riesgo, los CDC recomiendan que las mujeres embarazadas reciban una vacuna Tdap durante cada embarazo. Esto permite que los anticuerpos de la madre pasen al bebé antes del nacimiento.

En el pasado, las autoridades de salud promovían la estrategia del “cocooning” (vacunar a todos los miembros del hogar y cuidadores del bebé), pero en la práctica era difícil de implementar y ya no se recomienda como norma general. Vacunar a las mujeres embarazadas y a los bebés desde los 2 meses sigue siendo la protección más fuerte.

Mejor tecnología permite detectar más casos

Las pruebas modernas de PCR ayudan a detectar más casos de tos convulsa que en el pasado. Muchos centros de salud ahora usan rutinariamente esta tecnología de laboratorio para detectar varias infecciones respiratorias a la vez. Hace diez años, estas pruebas eran poco comunes.

Expertos de los CDC dicen que esto explica parte del aumento en los casos. Pero el elevado número de hospitalizaciones en bebés y el tamaño de los brotes en los estados demuestran que también ha aumentado la transmisión real.

Preocupa la resistencia a los antibióticos

Los médicos suelen tratar la tos ferina con antibióticos macrólidos, como eritromicina, azitromicina y claritromicina. Estos medicamentos funcionan mejor en las etapas iniciales de la enfermedad y ayudan a evitar que se propague. Otro medicamento, trimetoprim-sulfametoxazol, es una opción para algunos bebés y adultos.

Pero la tos convulsa resistente a macrólidos se ha vuelto común en otros países, especialmente en China, y reportes recientes muestran que la resistencia está aumentando en Perú. En Estados Unidos, los casos resistentes siguen siendo poco frecuentes.

Funcionarios de los CDC advierten que las cepas resistentes podrían propagarse más fácilmente a través de los viajes internacionales. Ya que las opciones de tratamiento son limitadas, especialmente para los bebés pequeños, el personal de salud está siguiendo esta situación de cerca.

Huang dijo que todavía no se han detectado casos de resistencia en el condado de Dallas. Pero está al tanto de la preocupación a nivel nacional.

¿Y ahora qué?

El resurgimiento de la tos ferina no tiene una sola causa. Se combinan varios factores: caída en la cobertura de vacunación, solo un 60% de las mujeres embarazadas recibe Tdap, disminución de la inmunidad, mejores herramientas de diagnóstico y señales tempranas de resistencia a los antibióticos.

Expertos en salud afirman que las soluciones deben ser tan complejas como el problema.

En todo el país, se les pide a los médicos estar atentos ante la posibilidad de la tos convulsa si ven pacientes —especialmente niños o personas que cuidan a recién nacidos— con tos persistente o ataques de tos seguidos de vómitos. Los bebés que dejan de respirar o se ponen morados deben recibir atención de inmediato.

Se anima a los obstetras a hablar sobre la vacuna Tdap en cada embarazo. También se insta a pediatras y médicos de familia a revisar el estado de los refuerzos en adolescentes y adultos.

Varios estados han lanzado alertas de salud en los últimos dos años, entre ellos Texas, que emitió alertas en 2024 y 2025 pidiendo a los médicos mantenerse atentos.

Huang dijo que el condado de Dallas trata de reconstruir sus programas de alcance comunitario que sufrieron recortes cuando terminó el financiamiento por covid. Pero el personal sigue siendo limitado. “Hay muchos factores que lo hacen más difícil”, afirmó.

También señaló que ahora este condado solo recibe los datos del registro de inmunizaciones una vez al mes, en lugar de cada día, lo que dificulta monitorear la cobertura. “Aún no lo tenemos… No es en tiempo real”, dijo.

Cómo proteger a los más pequeños

Con la temporada navideña cerca, expertos recomiendan a las familias con recién nacidos tomar precauciones adicionales:

• Asegurarse de que los bebés y los niños tengan sus vacunas al día, y de que todos los miembros del hogar estén al día con sus vacunas contra la gripe, covid y el virus respiratorio sincitial (VRS).
• No recibir a visitas enfermas.
• Buscar atención médica de inmediato si un bebé presenta tos o pausas en la respiración.

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Kennedy, a longtime anti-vaccine activist before seeking public office, claims that aluminum adjuvants are neurotoxic and tied to autism, asthma, autoimmune disease, and food allergies.

But science and medicine advances a different view. Strong recommendations that parents introduce peanut-containing foods to infants early, for instance, have led to a drop in the incidence rate of peanut allergies.

Since taking office, Kennedy has ordered reviews of vaccine ingredients, citing aluminum as a top concern. A discussion of “adjuvants and contaminants” is on the vaccine advisory panel’s draft agenda.

A Centers for Disease Control and Prevention webpage that for years has assured the public vaccines do not cause autism was updated Nov. 19 with new language stating that studies have not definitively ruled out a link between vaccines and autism.

He has also targeted scientists who have published studies showing aluminum adjuvants are safe. In August, Kennedy denounced a large Danish study finding no link between aluminum in vaccines and childhood disease, calling it a “deceitful propaganda stunt” and demanding its retraction. The Annals of Internal Medicine rejected the claim and refused to retract the study.

And, regarding the upcoming advisory panel meeting, HHS spokesperson Emily HIlliard said ACIP “is independently reviewing the full body of evidence on adjuvants and other vaccine components to ensure the highest safety standards.”

The stakes are high because Kennedy’s push to cast doubt on aluminum isn’t just about the ingredient itself. It’s part of a broader strategy to foster uncertainty about vaccine safety and lay the groundwork to challenge the National Vaccine Injury Compensation Program, which drug manufacturers say is essential to ensure a stable market for shots.

But researchers across infectious diseases, immunology, pediatrics, and epidemiology say the data is clear: Aluminum adjuvants are safe.

“Aluminum is the third most common element on the Earth’s surface,” said Paul Offit, a pediatrician and director of the Vaccine Education Center at Children’s Hospital of Philadelphia. “So we’re all exposed to aluminum all the time. The water that we drink has aluminum in it. The food that we eat has aluminum in it.”

Vaccines add only a tiny amount of aluminum to the body — a combined total of about 8 milligrams — after the schedule of childhood vaccines is complete. Offit said that over the first 18 years of life, people naturally take in about 400 milligrams of aluminum from everyday sources.

“I don’t know why there is so much concern,” said Rajesh Gupta, a former FDA vaccine scientist. “Aluminum gets distributed in the body everywhere. It is ultimately excreted by the kidneys in the urine. So, it is not that aluminum stays in the body.”

How They Work

The aluminum in vaccines isn’t foil or metal. It’s a compound of aluminum salts, such as aluminum hydroxide or aluminum phosphate, that help the vaccine work better.

It’s a bit like zinc in cold tablets: Patients don’t swallow chunks of metal, instead ingesting a zinc salt that dissolves safely in the body.

In vaccines, these aluminum salts give the immune system an extra nudge so it learns to recognize the target germ more effectively.

When injected, the vaccine stays near the injection site and causes mild, short-lived inflammation that summons immune cells. Those cells pick up the vaccine antigen, a harmless piece of a virus or bacterium, and carry it to nearby lymph nodes. There, the adjuvants show it around like a wanted poster so the body can identify and destroy the germ quickly.

Harm HogenEsch, a professor of immunopathology at the Purdue University College of Veterinary Medicine, said that aluminum adjuvants work only when they’re injected in the same spot as the vaccine ingredient they’re meant to boost, to help nearby immune cells learn to recognize the germ. If the two shots are given in different places, he said, “you don’t see that effect.”

In response to Kennedy’s claims, scientists say that anything that acts as an adjuvant can, in principle, also boost an allergic response. But that doesn’t mean aluminum-adjuvanted vaccines are turning children into food-allergic time bombs. Antigens in vaccines such as the hepatitis B surface antigen or HPV proteins are not allergens, and no food proteins are put into vaccines.

Animal Experiments

Animal studies form the basis of Kennedy’s claim that aluminum adjuvants in vaccines can create allergies. In these experiments, scientists deliberately sensitize rats or mice by injecting them with a food protein mixed with aluminum. The aluminum strengthens the immune response, but it does not cause an allergy by itself.

“That’s the basis for a lot of the experimental mouse models, where you inject a food allergen with an aluminum adjuvant to sensitize the mice,” HogenEsch said. “I’m not aware of any food antigen being included in vaccines, and so I don’t really see a way by which this could happen.”

Ross Kedl, a professor of immunology and microbiology at the University of Colorado Anschutz School of Medicine, went further, noting that there is no plausible route for vaccines to create a peanut allergy out of thin air. “Someone would have had to mix peanut proteins in with the actual vaccine prior to injection.”

Stefan H. E. Kaufmann, director emeritus at the Max Planck Institute for Infection Biology in Berlin, said results from mice often don’t match what happens in people, because “mice are much easier to push into allergic reactions than humans.” In other words, what looks dramatic in a rodent study doesn’t automatically apply to human immune systems.

And in this case, it’s “important to distinguish between how aluminum behaves in lab animals versus people,” Kaufmann said.

Human Studies

Beyond animal models and theoretical scenarios, scientists have looked hard for signals of harm in large human datasets.

In 2023, a study by the Vaccine Safety Datalink, a collaboration coordinated by the CDC, reported a slight increase in asthma among children with higher aluminum exposure before age 2, but the association disappeared in further analyses.

“That paper was roundly criticized,” Offit said. “When they controlled for breastfeeding, the association between asthma and receipt of aluminum-adjuvant-containing vaccines disappeared.”

“It should have never been published,” he said.

Kathy Edwards, professor emerita of pediatrics at Vanderbilt University, said that false signals are common when large databases are mined for dozens of outcomes.

“When you look at a hundred different things, just by the law of percentages, some of those may look like there is a signal,” she said. “The whole RFK Jr. assessment is really prone to cherry-picking,” she said, adding that “there does need to be some kind of basic understanding of statistics for people to interpret this.”

Soon after the 2023 U.S. findings drew attention, scientists at the CDC contacted Anders Hviid, head of epidemiology research at the Statens Serum Institut in Copenhagen, Denmark, to see whether his team could replicate the work.

“It makes perfect sense to try to replicate findings of any kind in different data sources,” Hviid said.

Hviid’s nationwide Danish study followed 1.2 million children over two decades, using linked national health registries that record every vaccination and diagnosis.

“Our health care system is quite egalitarian. It’s free, and there’s universal access. And everyone is in these nationwide registers,” he said. Their findings: no increased risk of these conditions associated with increasing amounts of aluminum received through the vaccines.

Rare Bumps

Doctors have documented one genuine reaction to aluminum adjuvants: itchy nodules at the injection site, called “pruritic granulomas.” These small bumps are so rare that most allergists and pediatricians will never see a single case.

This reaction “doesn’t lead to something bad, and it really isn’t associated with anything other than that local irritation,” Edwards said.

Researchers believe these bumps represent a localized immune response — meaning only in the area of the injection, not a body-wide allergy — that is very different from the kind of immediate allergic reaction people treat with antihistamines. These include the reactions driven by food or beestings, when histamine, the body’s own alarm signal, floods the system within minutes and causes hives, swelling, or breathing trouble. Kedl said that distinction often gets lost in public debate.

Eliminating Aluminum Adjuvants

For many experts, the real issue is not just whether aluminum is safe but what happens to the entire vaccine program if aluminum adjuvants are stripped out. For many modern vaccines that rely on a single purified protein — such as those for diphtheria and tetanus toxoids, hepatitis B, and HPV — adjuvants are crucial.

Edwards said that simply swapping in a different adjuvant isn’t realistic.

“They’re kind of all built on one another,” she said. Once a vaccine has been proved to work and become the standard of care, new or updated versions are generally no longer tested against a placebo in people who should be getting that vaccine. Instead, they’re tested against the existing product, which means each approval rests on the one before it.

Core childhood vaccines would probably have to be reformulated, and large clinical trials would have to be repeated to prove the new products are safe and effective. Meanwhile, production gaps and shortages would have to be managed, potentially for years, while manufacturers and regulators start over — all while diseases such as whooping cough, hepatitis B, and HPV-related cancers gain more room to spread.

“The aluminum adjuvants have sort of hit the sweet spot in terms of being effective at inducing a robust antibody response that is protective for those vaccines in which they’re being used and being very safe,” HogenEsch said. “It would be quite frankly foolish to try to eliminate them.”

A Century of Safe Use

The DTaP, hepatitis B, and HPV vaccines all contain aluminum adjuvants and have been in use for nearly a century. Large-scale studies show no link between aluminum and systemic allergic disease.

“We have had aluminum adjuvants in vaccines for decades,” Edwards said. “I have grandchildren. My grandchildren have received all of their vaccines. And I do not worry about the safety of them.”

If aluminum is falsely cast as the villain and vaccine uptake falls, experts warn, the consequences will not be theoretical: more measles in schools, more meningitis in college dorms, and more young adults dying of cancers that HPV shots could have prevented.

In their view, the real danger isn’t the trace amounts of a metal that children already encounter every day. It’s rolling back the protection aluminum-adjuvanted vaccines have provided for generations.

That’s the trade-off Offit hopes parents will see. “A choice not to get a vaccine is not a risk-free choice,” he said. “It’s just a choice to take a different risk.”

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El extenso estudio, realizado en Suecia, siguió a más de 2 millones de adolescentes y mujeres menores de 50 años durante más de una década. Los resultados muestran que, en general, los anticonceptivos hormonales son seguros. Sin embargo, también se identificaron pequeñas diferencias en el riesgo de cáncer de mama según los tipos de hormonas utilizadas en la composición. Además, se observó un leve aumento a corto plazo en los diagnósticos de cáncer de mama entre quienes ya los usaban o llevaban poco tiempo usando anticonceptivos.

Estos hallazgos coinciden con estudios anteriores, como un análisis danés publicado en 2017 y un metaanálisis de 2023 (Un metaanálisis en medicina es una técnica estadística que combina los resultados de múltiples estudios independientes para obtener una conclusión más precisa y robusta sobre un tema específico).

El estudio fue publicado en línea el 30 de octubre en JAMA Oncology.

Los médicos aseguran que los resultados no modificarán las recomendaciones actuales y que las mujeres no deberían dejar de usar sus anticonceptivos.

Aun así, en TikTok circulan advertencias basadas en hechos no concluyentes que afirman de manera falsa que los anticonceptivos causan cáncer y que son tan peligrosos como fumar. Defensores de la salud reproductiva advierten que investigaciones como esta pueden  fácilmente sacarse de contexto en las redes sociales y resumirse en una cifra alarmante.

Un ejemplo: el estudio reportó que las mujeres que habían usado anticonceptivos hormonales presentaban una tasa de cáncer de mama aproximadamente 24% más alta que quienes nunca los habían usado. Pero debido a que el cáncer de mama sigue siendo poco común en mujeres jóvenes, ese porcentaje representa un aumento de aproximadamente 54 a 67 casos por cada 100.000 mujeres al año: es decir, alrededor de 13 casos adicionales por cada 100.000 mujeres, o un caso adicional por cada 7.800 usuarias de anticonceptivos hormonales al año.

Las autoras del estudio, Åsa Johansson y Fatemeh Hadizadeh, epidemiólogas de la Universidad de Uppsala, explicaron que el aumento es leve y temporal, con un riesgo más alto durante el uso que disminuye entre cinco y diez años después de suspenderlo.

Rachel Fey, co-CEO interina de Power to Decide (organización que tiene como misión brindar información precisa sobre salud sexual y métodos anticonceptivos), afirmó que ese tipo de matices suelen perderse en redes sociales.

“Esto me enoja mucho porque está diseñado para asustar a personas como yo y alejarnos de los anticonceptivos, que han mejorado mi vida de muchas maneras”, dijo. “Es muy frustrante… especialmente cuando se presenta sin contexto. Y en esta era de redes sociales, ese contenido puede viralizarse sin que alguien con conocimiento lo ponga en perspectiva”.

El estudio también encontró que el riesgo era ligeramente mayor con ciertos progestágenos, como el desogestrel —presente en anticonceptivos orales combinados como Cyred EQ, Reclipsen, Azurette y Pimtrea—, pero no aumentaba con otros, como las inyecciones de acetato de medroxiprogesterona, que se venden bajo la marca Depo Provera.

Cómo interpretar los hallazgos

Algunos expertos advierten que los resultados deben analizarse con cautela, ya que el estudio contabilizó tanto casos de cáncer de mama invasivo como lesiones tempranas no invasivas conocidas como tumores in situ, crecimientos que pueden no llegar a ser peligrosos para la vida. Incluir estos casos precancerosos podría hacer que el riesgo total de una enfermedad clínicamente importante parezca más alto de lo que realmente es.

“Una proporción considerable de los ‘casos’ nunca habría evolucionado hacia un cáncer de mama invasivo”, explicó Lina S. Mørch, investigadora principal y líder de equipo en el Instituto del Cáncer de Dinamarca, quien no participó en el estudio sueco. Agregó que sería conveniente esperar más datos que distingan entre cánceres en etapa temprana y avanzada antes de emitir nuevas recomendaciones sobre hormonas específicas.

La charla médico-paciente

Aunque los científicos debaten sobre cómo interpretar ciertos detalles del estudio, los médicos enfatizan que, para la mayoría de los pacientes, este estudio refuerza lo que ya suelen conversar en consulta: que los anticonceptivos hormonales son en general seguros y que las decisiones deben basarse en las necesidades y valores de cada mujer.

Katharine White, jefa de Obstetricia y Ginecología del Centro Médico de Boston, dijo que este estudio no cambiará la manera en que aconseja a sus pacientes.

“Cuando oriento a mis pacientes sobre las opciones anticonceptivas, me enfoco en sus experiencias previas, su historial médico y lo que es importante para ellas respecto a su método de anticoncepción y la planificación del embarazo (si aplica)”, escribió en un correo electrónico. “Los efectos secundarios y riesgos ya son parte clave de la información que brindo sobre métodos hormonales y no hormonales”.

Otros médicos también señalaron que existen opciones sin hormonas.

Eleanor Bimla Schwarz, jefa de Medicina Interna en el Hospital General Zuckerberg San Francisco, dijo que “para quienes prefieren métodos anticonceptivos sin hormonas, el DIU de cobre ofrece una opción segura, conveniente y altamente efectiva por más de una década, y puede retirarse fácilmente si se desea un embarazo”, refiriéndose a un tipo de dispositivo intrauterino de larga duración.

Mary Rosser, directora de Salud Integral de la Mujer en el Centro Médico Irving de la Universidad de Columbia, opinó que este fue un estudio amplio y de alta calidad que analizó muchos tipos de hormonas durante varios años. Pero también dijo que aún no se deben cambiar las recomendaciones médicas.

Johansson y Hadizadeh destacaron que los resultados deben servir para una toma de decisiones compartida, no para generar alarma. “Puede ser razonable considerar formulaciones asociadas con un riesgo más bajo según nuestros datos”, señalaron.

Indicaron que los productos con acetato de medroxiprogesterona, drospirenona o levonorgestrel se vincularon con un menor riesgo, mientras que podría ser mejor evitar el uso prolongado de anticonceptivos que solo contienen desogestrel, si hay otras opciones adecuadas.

Poner el riesgo en perspectiva

Los anticonceptivos hormonales ofrecen muchos beneficios para la salud más allá de prevenir embarazos. Pueden reducir el sangrado menstrual abundante, aliviar el dolor causado por la endometriosis y disminuir el riesgo de cáncer de ovario y útero incluso años después de suspenderlos. Mørch indicó que hasta los riesgos pequeños deben discutirse, pero que las decisiones deben basarse en los “valores y preferencias” de cada mujer.

White resaltó la importancia de ver el panorama completo. “El riesgo de un embarazo no planificado es del 85% en quienes no usan ningún método anticonceptivo, por lo que cualquier riesgo asociado con los anticonceptivos debe analizarse en comparación con el riesgo de un embarazo inesperado”, escribió.

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The outbreaks are fueled by falling vaccination rates, fading immunity, and delays in public health tracking systems, according to interviews with state and federal health officials. Babies too young to be fully vaccinated are most at risk.

“Pertussis cases increase in a cyclical fashion driven by waning immunity, but the size of the outbreak and the potential for severe outcomes in children who cannot be vaccinated can be mitigated by high coverage and good communication to folks at risk,” said Demetre Daskalakis, a former head of the Centers for Disease Control and Prevention’s immunization program, who resigned in August.

Before the first pertussis vaccine became available in the early 1900s, whooping cough was one of the most common childhood diseases and a major cause of childhood death in the United States. Today, children get a series of DTaP shots (full-dose version) starting at 2 months old, and teens and adults receive a Tdap booster (lower-dose version) every 10 years. (Both vaccines target diphtheria and tetanus in addition to pertussis.)

Until recently, 8 in 10 toddlers had received four doses of the DTaP vaccine by age 2, and case rates were controlled. But vaccine coverage has declined since the covid pandemic and increases in state nonmedical exemptions have widened immunity gaps, which is when the proportion of individuals who are immune falls below the level needed to contain spread.

Texas logged 1,928 pertussis cases in 2024. By October 2025, the state had exceeded 3,500. National numbers are just as stark: In the first three months of 2025, the U.S. tallied 6,600 cases — four times last year’s pace and 25 times 2023’s. Several states are posting their highest case totals in a decade, and outbreaks from Louisiana to South Dakota to Idaho make clear this surge isn’t regional. It’s everywhere.

Key Factors Behind These Numbers

Texas lawmakers recently passed a law that made it easier for parents to claim nonmedical exemptions from school vaccine requirements by allowing them to download exemption forms online. These forms now go straight to schools, not health departments, making the exemptions harder to track.

Dallas County Health and Human Services Director Phil Huang said the full impact of the new exemption rule is not yet known because it began this school year, but he expects it will make school-level vaccination rates fall even more.

He’s already noted a dramatic drop in vaccinations. Normally, during back-to-school season, “our whole front downstairs area is packed,” he said. “We did not see that this year.”

Huang believes fear of immigration enforcement may be keeping at least some families, especially Hispanic families, from getting vaccinated. Dallas County is about 40% Hispanic. “We think that a lot of them are deterred by the ICE activity,” he said, referring to Immigration and Customs Enforcement.

More complications: These vaccines protect against severe disease, but protection against infection fades over time, as is the case with the covid and influenza vaccines.

The U.S. switched in the 1990s from whole-cell pertussis vaccines to “acellular” ones, which cause fewer side effects but do not last as long. Because more adults today than in the past received the acellular vaccine as children, many have lost immunity over time and may unknowingly pass the infection to babies.

Babies Face the Greatest Risk

Whooping cough is especially dangerous for infants under a year old. Some stop breathing during coughing fits. Many need hospital care, about 1 in 5 of whom develop pneumonia, and about 1% of whom die.

Because of this high risk, the CDC urges pregnant women to get a Tdap vaccine during every pregnancy. This allows the mother’s antibodies to pass to the baby before birth.

Health officials once promoted “cocooning,” vaccinating all family members and caregivers around the baby, but that strategy was hard to carry out in real life and is no longer widely recommended. Vaccination of pregnant women and babies at 2 months of age remains the strongest protection.

Better Testing Finds More Cases

Modern PCR testing is also uncovering more pertussis cases than in the past. Many clinics now routinely use this lab-based technology to test for several respiratory infections at once, including pertussis. Ten years ago, these panels were uncommon.

CDC experts say this explains part of the rise in case counts. But the large number of infant hospitalizations and the size of state outbreaks show that true transmission has also increased.

A Growing Worry: Antibiotic Resistance

Doctors normally treat pertussis with macrolide antibiotics, such as erythromycin, azithromycin, and clarithromycin. These drugs work best early in the illness and help stop spread. Another drug, trimethoprim-sulfamethoxazole, is an option for some older infants and adults.

But macrolide-resistant pertussis has become common abroad, especially in China, and recent reports show resistance rising in Peru. In the U.S., resistant cases have been rare.

CDC officials warn that resistant strains could spread more easily through international travel. Because treatment options are limited, especially for very young infants, health workers are watching this closely.

Huang said macrolide resistance has not been seen yet in Dallas County. But he is aware of the national concern.

What Happens Now

The resurgence of whooping cough has no single cause. Instead, several problems are occurring at once: falling vaccine coverage, only about 60% of pregnant women receiving Tdap, waning immunity, improved testing, and early signs of antibiotic resistance.

Health experts say solutions must match the problem’s complexity.

Across the nation, clinicians are being told to have a higher suspicion for pertussis when they see patients, especially children or caregivers of newborns with a persistent cough or coughing fits followed by vomiting. Babies who stop breathing or turn blue need immediate care.

Obstetricians are encouraged to discuss Tdap during every pregnancy. Pediatricians and family doctors are urged to check booster status for teens and adults.

Several states have issued health advisories over the past two years, including Texas, which has issued alerts in both 2024 and 2025 urging clinicians to stay vigilant.

Huang said Dallas County is trying to rebuild public health outreach programs that were cut when covid funding ended. But staffing is still limited. “There’s just a lot of different things that are making it more difficult,” he said.

He also noted that Dallas County now receives immunization registry data only once a month, rather than daily, making it harder to track vaccine coverage. “We don’t have that yet. … It’s not real time,” he said.

Protecting the Youngest

As the holiday season approaches, experts urge families with newborns to take extra care:

• Ensure infants and children are up to date with their childhood vaccines and that everyone in the family is up to date with their vaccines for influenza, covid, and RSV, or respiratory syncytial virus.
• Keep sick visitors away.
• Seek care quickly if an infant has a cough or pauses breathing.

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The massive study, which was conducted in Sweden and tracked more than 2 million teenage girls and women under age 50 for more than a decade, found that hormonal contraception remains safe overall, but also found small differences in breast cancer risk based on the hormones used in the formulation. In addition, the researchers observed a small, short-term rise in breast cancer diagnoses among current or recent users. Those findings are consistent with prior large studies, including a 2017 Danish registry analysis and a 2023 meta-analysis.

It was published online Oct. 30 in JAMA Oncology.

Doctors say these study results won’t change how they advise patients and that women should not stop using their birth control.

Still, TikTok is flooded with factually incomplete warnings that contraceptives cause cancer and are as dangerous as smoking. Reproductive health advocates warn that studies like this can easily be taken out of context online and be reduced to a single alarming number.

Case in point: The study reported that women who had used hormonal birth control had about a 24% higher rate of breast cancer than women who hadn’t. But because breast cancer is still uncommon in younger women, that works out to an increase from roughly 54 to 67 breast cancer cases per 100,000 women per year — about 13 extra cases per 100,000 women, or about one extra case per 7,800 users of hormonal contraceptives per year.

Co-authors Åsa Johansson and Fatemeh Hadizadeh, epidemiologists at Uppsala University, said the rise is modest and short-term, with risk highest during current use and fading within five to 10 years after stopping.

Rachel Fey — interim co-CEO of Power to Decide, a group whose mission is to provide accurate information on sexual health and contraceptive methods — said that kind of nuance is exactly what tends to disappear on social media. “I get really angry at this because it’s designed to scare people like me away from birth control, which has made my life so much better in so many ways,” she said. “It’s really frustrating … especially when it’s given without context. And then in this era of social media, it can just take off without anybody who knows what they’re talking about providing that context.”

The researchers also found the risk was slightly higher with certain progestins such as desogestrel — found in combined oral contraceptives like Cyred EQ, Reclipsen, Azurette, and Pimtrea — but did not increase with others, such as medroxyprogesterone acetate injections, sold under the brand name Depo‑Provera.

How To Interpret the Findings

Some experts say the results should be viewed with care because the study counted both invasive breast cancers and early, noninvasive lesions known as in situ tumors, growths that may never become life-threatening. Including these precancerous cases could make the overall risk of clinically significant disease appear higher than it is.

“A substantial proportion of the ‘cases’ would never have progressed to invasive breast cancer,” said Lina S. Mørch, a senior researcher and team leader at the Danish Cancer Institute. Mørch was not associated with the Swedish study. She added that experts should wait for more data separating early-stage and advanced cancers before making new rules or warnings about specific hormones.

The Doctor-Patient Conversation

Even as scientists debate how to interpret the finer points of the data, physicians emphasize that for most patients, the study reinforces what they already discuss in the exam room: that hormonal birth control is broadly safe, and decisions should be tailored to each woman’s needs and values.

Katharine White, chief of Obstetrics and Gynecology at Boston Medical Center, said this study won’t change how she talks to her patients.

“When counseling patients about their contraceptive options, I focus on their past experiences with birth control, their medical history, and what’s important to them about their birth control method and pregnancy planning (if applicable),” White wrote in an email. “Side effects and risks of methods are already a key part of my counseling about both hormonal and non-hormonal methods.”

Other doctors noted there are other contraceptive options.

Eleanor Bimla Schwarz, chief of General Internal Medicine at Zuckerberg San Francisco General Hospital, said, “For those who prefer hormone-free contraception, the copper IUD offers safe, convenient, highly effective contraception for over a decade after placement, and is rapidly reversible when pregnancy is desired,” referring to a type of long-acting intrauterine device.

Mary Rosser, director of Integrated Women’s Health at Columbia University Irving Medical Center, said this was a large, high-quality study that looked at many types of hormones over many years. But she added that doctors shouldn’t change their advice yet.

Johansson and Hadizadeh stressed that the results should guide shared decision-making, not cause alarm. “It may be reasonable to consider formulations associated with lower observed risk in our data,” they said. They noted that products containing medroxyprogesterone acetate, drospirenone, or levonorgestrel were linked to lower risk, while long-term use of desogestrel-only contraceptives might be best avoided when other options fit.

Keeping the Risk in Perspective

Hormonal birth control provides many health benefits beyond pregnancy prevention. It can lighten heavy periods, ease pain from endometriosis, and lower the risk of ovarian and uterine cancers for years after stopping. Mørch noted that even small risks are worth discussing but said decisions should be guided by women’s “values and preferences.”

White said it’s important to see the big picture. “The risk of an unintended pregnancy is 85% for people who do not use contraception—so any risks of birth control need to be weighed against the risk of an unexpected pregnancy,” she wrote.

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The increase in risk was small for any one child, but because millions of women were pregnant during the pandemic, even a small increase matters. The study doesn’t prove that covid infection during pregnancy causes autism or other brain conditions in the fetus, but it suggests that infections and inflammation during pregnancy can affect how a baby’s brain grows, something scientists have seen before with other illnesses. It’s a reason to help pregnant women avoid covid and to keep a close eye on children who were exposed in the womb.

What the Study Found

Researchers at Massachusetts General Hospital examined medical records from more than 18,000 mothers and their children born from March 2020 through May 2021, before vaccines were widely available to pregnant women. Because everyone giving birth during that period was tested for covid, the team could clearly see which pregnancies were exposed to the virus causing it.

About 5% of those mothers had covid while pregnant. Their children were modestly more likely to be diagnosed with a neurodevelopmental condition by age 3 than those whose mothers weren’t infected, even after accounting for differences in maternal age, race, insurance status, and preterm birth.

The link appeared strongest among boys and when infection occurred in their mother’s third trimester. Still, most children in both groups showed typical development.

“This was a very clean group to follow,” said Andrea Edlow, a maternal-fetal medicine specialist at Mass General and one of the study’s authors. “Because of universal testing early in the pandemic, we knew who had covid and who didn’t.”

Independent authorities say covid, which causes a powerful immune response in some people, fits the biological pattern seen with other infections in pregnancy. Alan Brown, a professor of psychiatry and epidemiology at Columbia University who studies maternal infection and brain development and was not involved in this research, explained, “Covid would be a very strong candidate for it to happen because the amount of inflammation is very extreme.”

How Might Infection Affect Brain Development?

Scientists are still piecing together how various infections during pregnancy can affect fetal development. Severe illness can cause inflammation that disrupts brain growth or can trigger preterm birth, which carries its own risks.

“There’s a long history of evidence showing that maternal infection can slightly raise the risk for many neurodevelopmental disorders,” said Roy Perlis, the vice chair for research in psychiatry at Massachusetts General Hospital and co-author of the new study.

Edlow’s lab is investigating how infection and inflammation may interfere with brain development. In a healthy brain, immune cells help shape developing neural circuits by trimming away extra or unnecessary connections, a process known as “synaptic pruning,” which sculpts the brain’s wiring. When a mother’s immune system is activated by infection, inflammatory molecules can reach the fetal brain and alter the pruning process.

Animal studies support Edlow’s hypothesis. When scientists trigger inflammation in pregnant mice, their offspring often show changes in how brain cells grow and connect, changes that can alter learning and behavior.

Why Late Pregnancy and Why Boys?

In Edlow and Perlis’ study, the link between covid and developmental delays was strongest when infection occurred late in pregnancy, during the third trimester. That’s also when the fetal brain is growing most rapidly, forming and refining millions of neural connections.

“When we think of organ development, we think earlier in pregnancy, but the brain is an exception in this regard, where there’s a massive amount of brain development in the third trimester. And that continues after birth,” Perlis said. “It is entirely plausible that the third trimester is a period of vulnerability specifically for brain development.”

But not all researchers agree that the third trimester is uniquely vulnerable. Brian Lee, a professor of epidemiology at Drexel University, cautioned that because most mothers in the study were tested at delivery, there were simply more late-pregnancy infections to analyze. “That gives the study more power to find a difference in the third trimester,” he said. “It doesn’t prove earlier infections aren’t important.”

The study also found stronger effects in boys. That pattern is familiar: Boys are generally more likely than girls to have speech or motor delays and to be diagnosed with autism. Researchers suspect that male fetuses may be more susceptible to stress and inflammation, though the biology isn’t fully understood.

What the Study Can and Can’t Show

Edlow and Perlis are careful to say the study shows an association, not proof that covid infection in pregnancy causes developmental problems. Many other factors could explain the correlation.

Mothers who get sick with covid may have other health issues, such as obesity, diabetes, or mental health conditions, that increase the risk of developmental delays in children. “Persons with mental disorders are much more likely to get covid. Women with mental disorders are much more likely to have kids with neurodevelopmental problems,” Lee said. “Mothers with worse physical health are also at higher risk of having children with neurodevelopmental problems.”

Lee’s research has shown that even infections before or after pregnancy can be linked to autism, suggesting that shared genetics or environment, rather than the infection itself, could be at play. That’s why experts say much larger, longer studies are needed to understand the extent of any risk from the infection.

Edlow, Perlis, and their team plan to follow the children in their study as they grow older to see whether early differences persist or fade. They’re also studying how inflammation during pregnancy affects the placenta and fetal brain, and how to counteract these effects.

What About Vaccination?

Because this study followed pregnancies from early in the pandemic, it doesn’t answer whether vaccination changes the risk. But other research offers reassurance.

A large national study in Scotland found no difference in early developmental outcomes between children whose mothers were vaccinated and those who weren’t. Another study in the U.S. found the same: no link between prenatal covid vaccination and developmental delays through 18 months. Both align with decades of data showing that vaccination during pregnancy is safe for both the mother and the baby.

“Vaccination is a short spike … your immune system revs up, then it goes back to normal,” Edlow said. “Covid [infection] is much more prolonged, unpredictable, and people can get … a dysregulated immune phenomenon that really doesn’t exist in vaccine responses.”

What This Means for Parents and Clinicians

Since late 2020, there’s been widespread confusion and misinformation about the safety of covid vaccination during pregnancy. Some women have hesitated to get vaccinated out of fear it might harm their baby. But the evidence since then has been clear: Covid vaccines are safe in pregnancy. The American College of Obstetricians and Gynecologists strongly recommends covid vaccination to protect both mother and child.

Experts say the broader lesson is that pregnancy is a period of vulnerability, and prevention matters, not only for covid, but other infections as well.

Janet Currie, a professor of economics at Yale University, said these risks remain “underappreciated,” despite decades of evidence. “Even though the flu vaccine is recommended for pregnant women, very few pregnant women get it,” she said. “Physicians seem to be reluctant to vaccinate pregnant women.”

As Gil Mor, scientific director of the C.S. Mott Center for Human Growth and Development at Wayne State University in Detroit, put it, “Protecting the mother is protecting the long-term health of the offspring. … The best intervention is vaccination.”

A Century-Old Echo

The idea that what happens in the womb can shape life after birth took root with studies of famine, like the Dutch “Hunger Winter” in the final months of World War II. In 1944 and 1945, as German forces blockaded the western Netherlands, rations fell to just a few hundred calories a day. Thousands died of starvation, and women pregnant during that period gave birth to babies who later faced higher risks of heart disease, diabetes, and schizophrenia. The episode became a cornerstone of the “fetal origins” idea, that deprivation or stress in pregnancy can have lifelong effects.

The 1918 flu pandemic broadened that idea to infection. Babies exposed to influenza in utero later showed small but lasting differences in education and earnings, a sign that illness during pregnancy could affect brain development. Researchers in Taiwan, Sweden, Switzerland, Brazil, and Japan found similar consequences. Some argued that those findings reflected the disruptions of World War I, not the flu itself. But later studies, including those from the United Kingdom and Finland, have strengthened the case for a biological effect, reinforcing that the infection itself, not wartime upheaval, was the key driver.

“It isn’t simply influenza that can alter fetal neurodevelopment,” Kristina Adams Waldorf, a professor of obstetrics and gynecology at the University of Washington, explained. “Many types of infections … in the mother can be transmitted as a signal to the fetus, which can alter its brain development.”

A century later, the same question has returned with covid: Could infection during pregnancy subtly shape how children grow and learn? The new Massachusetts General Hospital study offers an early look at an answer.

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“People don’t realize how much these clinics hold together the local health system until they’re gone,” said George Hill, the group’s president and CEO. “For thousands of patients, that was their doctor, their lab, and their lifeline.”

Maine Family Planning’s closures are among the first visible signs of what health leaders call the biggest setback to reproductive care in half a century. The U.S. Department of Health and Human Services’ Office of Population Affairs, which administers the Title X family planning program, has been effectively shut down. At the same time, Medicaid cuts, the potential lapse of Affordable Care Act subsidies, as well as cuts across programs in the Health Resources and Services Administration and Centers for Disease Control and Prevention are eroding the broader safety net.

“When you cut OPA, HRSA, and Medicaid together, you’re removing every backup we have,” said Clare Coleman, president of the National Family Planning and Reproductive Health Association. “It’s like taking EMTs off the road while closing the emergency rooms.”

Asked about the cutbacks, HHS press secretary Emily G. Hilliard said, “HHS will continue to carry out all of OPA’s statutory functions.”

How the Safety Net Frays

For more than 50 years, Title X has underwritten a national network of clinics, now numbering over 4,000, that provide contraception, pregnancy testing, testing and treatment for sexually transmitted infections, cancer screening, and other primary and preventive care to nearly 3 million low-income or uninsured patients annually. OPA managed nearly $400 million in grants, issued clinical guidance, and ensured compliance.

In mid-October, OPA’s operations went dark amid federal layoffs that also affected hundreds of CDC staffers. “Under the Biden administration, HHS became a bloated bureaucracy — expanding its budget by 38% and its workforce by 17%,” a spokesperson for the department said at the time, adding, “HHS continues to eliminate wasteful and duplicative entities, including those inconsistent with the Trump administration’s Make America Healthy Again agenda.”

According to Jessica Marcella, who led OPA under the Biden administration, the office was previously staffed by 40 to 50 people. Now, she says, only one U.S. Public Health Service Commissioned Corps officer remains.

“The structure to run the nation’s family planning program disappeared overnight,” said Liz Romer, OPA’s former chief clinical adviser.

“This isn’t just about government jobs,” Coleman said. “It’s a patient care crisis. Every safety net program that touches reproductive health is being weakened.”

A Policy Linking Health, Autonomy, and Opportunity

Created in 1970 under President Richard Nixon and rooted in President Lyndon Johnson’s War on Poverty, Title X was designed as a cornerstone of preventive public health, not a partisan cause. Nixon called family planning assistance key to a “national commitment to provide a healthful and stimulating environment for all children,” and Congress agreed overwhelmingly across party lines.

Sara Rosenbaum, a professor of health law at George Washington University, said the program reflected a pivotal shift in how policymakers understood health itself.

“By the late 1960s, there was a deep appreciation that the ability to time and space pregnancies was absolutely essential to women’s and children’s health,” she said. “Title X represented the idea that reproductive care wasn’t a privilege or a moral issue. It was basic health care.”

UCLA economist Martha Bailey later found that children born after the first federally funded family planning programs were 7% less likely to live in poverty, and had household incomes 3% higher, than those born before. Research by Bailey just published by the National Bureau of Economic Research showed that when low-income women can access free birth control, unintended pregnancies drop by 16% and abortions drop by 12% within two years.

Those findings underscore what Rosenbaum calls “one of the great public health achievements of the 20th century — a program that linked economic opportunity to health and autonomy.”

That bipartisan foundation and evidence-based mission, Rosenbaum said, make today’s unraveling especially striking.

“What was once common sense, that access to family planning is essential to a functioning health system, has become politically fragile,” she noted. “Title X was built for continuity, but it’s being undone by neglect.”

The Hidden Health Risks Behind Unplanned Pregnancies

Family planning is central to maternal and infant health because it gives women the time to optimize medical conditions like high blood pressure, diabetes, and heart disease before pregnancy, and allows them to safely space out their births.

“Pregnancy is the ultimate stress test,” said Andra James, a maternal-fetal medicine specialist who advised the CDC on its contraceptive guidelines. “It increases the heart’s workload by up to 50%. For people with heart disease, diabetes, or hypertension, that stress can be dangerous.”

Brianna Henderson, a Texas mother, learned this firsthand. Weeks after delivery, she developed peripartum cardiomyopathy, a form of heart failure that can occur during or after pregnancy. She survived. Her sister, who had the same undiagnosed condition, died three months after giving birth to her second child. Those kids are now 12 and 16, and they’re growing up without a mom. Their dad and his mother look after the kids now.

“Contraception has been a lifesaving option for me,” Henderson said.

James and other specialists warn that without CDC-informed guidance on contraceptive safety for complex conditions, clinicians and patients are left without clear, current standards.

What History and the Data Predict Happens Next

Title X clinics provide millions of STI tests each year and are often the only cancer screening sites for uninsured women. Cuts to Medicaid and ACA subsidies will make it even harder for people to afford preventive visits.

“If these clinics close, we’ll see more infections, more unplanned pregnancies, and more maternal deaths, especially among Black, Indigenous, and rural communities,” said Whitney Rice, an expert on reproductive health at Emory University.

And the geographic gaps are large already. Power to Decide, a nonprofit reproductive rights group, counts more than 19 million women living in “contraceptive deserts,” where there’s no reasonable access to publicly supported birth control. 

“These are places where the nearest clinic might be 60 or 100 miles away,” said Power to Decide interim co-CEO Rachel Fey. “For many families, that distance might as well be impossible.”

The High Price of Short-Term Savings

Each pregnancy averted through Title X saves about $15,000 in public spending on medical and social services, according to an analysis by Power to Decide. And an analysis by the Guttmacher Institute shows that every $1 invested in publicly funded family planning programs saves roughly $7 in Medicaid costs.

Cutting federal funding for reproductive health services “isn’t saving money. It’s wasting it,” said Brittni Frederiksen, an associate director with KFF’s Women’s Health Policy program and a former OPA health scientist. “We’ll spend far more fixing the problems these cuts create.” KFF is a health information nonprofit that includes KFF Health News.

Supporters of cuts argue federal spending must be reduced and states should set their own priorities.

Strain on the Ground

Affirm, Arizona’s Title X grantee, oversees a statewide network of clinics that provide family planning services to more than 33,000 patients each year.

Affirm CEO Bré Thomas said the state could lose $6.1 million in Title X funding if federal appropriations expire after March 31. It’s a cut that would reduce access to care across the network. “That’s $6.1 million for Arizona,” she said. “That means over 33,000 patients in our state could lose access to services.”

Thomas noted that two consecutive funding reductions, combined with 11 years of flat federal support and rising health care costs, have already strained operations. Without new funding, she warned, clinics may be forced to limit contraceptive options to cheaper methods, reduce preventive care, and lay off staff, especially in rural communities. “We’re talking about impacts to people’s jobs and their ability to access the care they need,” she said.

Megan Kavanaugh, a scientist at the Guttmacher Institute, underscored those limits.

“Federally Qualified Health Centers do not have the capacity to absorb the number of patients who will lose care,” she said, referring to federally funded community-based clinics for underserved populations. “Some people may find another clinic, but a large share simply won’t, and we’ll see that reflected in higher rates of unintended pregnancy, untreated infections, and later-stage disease.”

Hospitals are beginning to absorb the spillover.

“The safety net is shrinking, and hospitals can’t absorb everyone,” said Sonya Borrero, a reproductive health expert at the University of Pittsburgh School of Medicine and a former chief medical and scientific adviser at OPA. “Wait times will get longer, and preventable problems will rise.”

Funding Frozen, Oversight Halted

With OPA offline, Title X dollars already awarded can be spent, but no new funds are moving.

“Most programs can hang on for a few months,” Romer said. “By spring, many won’t have enough money to stay open.”

The halt also suspends compliance reviews and technical assistance tied to CDC-aligned guidelines.

Marcella, the former OPA leader, warned of a “backdoor dismantling.”

“If there aren’t people to administer the grants, then the administration can later argue the program isn’t working and redirect the funds elsewhere,” she said. “This is a functional elimination, done quietly.”

Kavanaugh called the moment “one more step toward dismantling the public health infrastructure that has supported people’s reproductive health for decades.”

Without staff to move money and guidance, she said, “that’s how a system collapses.”

What Can Still Be Done

According to the National Association of Community Health Centers, Federally Qualified Health Centers can still use HRSA money that was already approved, even during the government shutdown. But no new funding is being released, similar to the freeze on Title X funds. At the same time, HRSA has stopped first-quarter payments for its Title V Maternal and Child Health program, which limits how states can provide preventive care and services for children and young people with special health needs.

Some states — California, New Mexico, Washington — are plugging holes with state dollars, and health systems are expanding telehealth, but most jurisdictions cannot replace federal support at scale.

“Private donors can’t replace the federal government,” said Hill, of Maine Family Planning. “You can’t crowdfund your way to a working health system.”

Congress could restore Title X and rebuild OPA’s staffing, but without administrators in place, money can’t reach clinics quickly. States have a short window to bridge care by stabilizing Medicaid coverage, shoring up community health centers, and protecting contraceptive access.

“This isn’t a political debate,” Romer said. “It’s women showing up for care and finding the doors locked.”

KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF—an independent source of health policy research, polling, and journalism. Learn more about KFF.

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