ACOG's 2026-27 respiratory virus immunization recommendations in pregnancy, postpartum

The American College of Obstetricians and Gynecologists (ACOG) has released updated guidance that strongly recommends vaccination against COVID-19, respiratory syncytial virus (RSV), and influenza for all women who are pregnant, postpartum, or contemplating pregnancy ahead of the 2026–27 respiratory virus season. Notable updates detailed further below include an extension in the RSV vaccine eligibility window and the inclusion of a table for appropriate usage for FDA-approved influenza vaccines.¹

The recommendations are based on the latest safety and efficacy data and were informed by an independent evidence review completed by the Vaccine Integrity Project (VIP), a program of CIDRAP at the University of Minnesota, in collaboration with the American Medical Association (AMA).^1,2

The VIP evidence review screened thousands of peer-reviewed studies published since August 2025 and found that immunizations against all 3 viruses continue to provide meaningful protection against severe illness, hospitalization, and death, with no new safety concerns identified in comparative studies.² The review informed coordinated recommendations released by ACOG, the American Academy of Pediatrics (AAP), the American Academy of Family Physicians, and the Infectious Diseases Society of America.^1,2

“Vaccination is standard preventive care, and complications can occur in pregnancy as a result of not being vaccinated that are completely preventable,” said ACOG President Camille A. Clare, MD, MPH, CPE, FACOG. “Unfortunately, we are living in challenging times when it comes to the large amount of vaccine misinformation and disinformation that exists today, so even more responsibility falls to ob-gyns to combat that and make sure patients know the facts.”¹

COVID-19 vaccination in pregnancy

Despite strong evidence supporting COVID-19 vaccination during pregnancy, 11.1% of pregnant women received a COVID-19 vaccine during the 2025–26 respiratory virus season, down 25.7% from the previous year.¹ The lowest vaccination rates are among Hispanic and Black pregnant women, reflecting persistent inequities in access, distribution, and uptake.¹

The VIP noted that though COVID-19 has become “substantially less severe” compared to the height of the pandemic (peak weekly COVID-19 hospitalization rate in the 2025-26 season was 2.0 per 100,000 people), infection can still cause signficant illness, specifically for older adults, infants, and pregnant individuals.

Based on the evidence review, vaccination reduced the risk of severe disease in pregnancy, hospitalization, and adverse outcomes including stillbirth and preterm birth.¹ Findings revealed that maternal COVID-19 vaccination lowered the risk of emergency department and urgent care visits for pregnant women by 58%, and extended protection to infants, with vaccine effectiveness of 50% to 54% against COVID-related hospital contacts in the first 2 months of life regardless of which trimester the vaccine was received.^2,3

ACOG’s strong recommendation is now based on more than 5 years of research and millions of administered doses, with no increased risk of miscarriage, stillbirth, preterm birth, small-for-gestational-age birth, or birth defects identified.¹ There are currently 4 FDA-approved COVID-19 vaccines, all of which are safe in pregnancy, stated the women’s health society.¹

“It has been well established that COVID-19 vaccination does not cause pregnancy loss even when administered in the first trimester,” said Mark Turrentine, MD, FACOG, lead author of the guidance. “The true risk to pregnant people and their pregnancies is from COVID-19 infection, especially for those with preexisting health conditions. Vaccination remains the best way to mitigate that risk.”¹

Michael T. Osterholm, PhD, MPH, the Vaccine Integrity Project’s executive director, agrees, adding another year of review continues to support maternal vaccination.

“Immunization continues to be one of our best tools for preventing severe illness from respiratory viruses,” said Osterholm in a statement. “This year’s review confirms that the newest evidence remains consistent with research showing these immunizations reduce the risk of hospitalization and death among the people most likely to experience serious disease.”

RSV vaccination in pregnancy

A notable change in the 2026–27 guidance is that ACOG now recommends pregnant individuals receive a single dose of the bivalent RSV PreF vaccine (Abrysvo; Pfizer) between September 1 and March 1, an extension from the prior January 31 end date. This change reflects that recent RSV seasons have occurred later in the spring and have become more severe. The change comes as 41.6% of eligible pregnant individuals have received the maternal RSV vaccine, according to ACOG.¹

The vaccine should be administered between 32 0/7 and 36 6/7 weeks of gestation for those without a planned delivery within 2 weeks, according to ACOG.¹ The bivalent RSV PreF vaccine remains the only FDA-approved RSV vaccine for use in pregnancy and should only be received once, as there are no data on effectiveness in subsequent pregnancies. If the vaccine is not administered during pregnancy, infants should receive one of 2 available monoclonal antibodies, clesrovimab or nirsevimab, at birth, aligning with previous guidance from ACOG and the AAP.

The VIP evidence review found that maternal RSV vaccination reduced the risk of infant hospitalization by 51% to 70%, while the infant monoclonal antibody nirsevimab reduced the risk of RSV-related hospitalization by 63.6% to 93% within the first RSV season.²

“All pregnant patients should take RSV seriously,” said Brenna Hughes, MD, FACOG, lead author of the RSV Practice Advisory. “Every year we see as many as 80,000 children under the age of five being hospitalized because of RSV, and the highest rate is among babies that are 6 months old or younger. It is imperative that either patients are vaccinated or infants receive one of the monoclonal antibodies. We recommend that clinicians consider which option is most readily available and easily accessible when counseling patients.”¹

Influenza vaccination in pregnancy

The 2026–27 guidance includes a new table of recommendations covering all FDA-approved influenza vaccines. Although the table includes the newly approved mRNA vaccine mRNA-1010, that product is not approved for use in pregnancy and has no data for lactating individuals. Inactivated or recombinant influenza vaccines remain the only options recommended in pregnancy in any trimester.

The VIP evidence review found that influenza vaccination during pregnancy improved protection against symptomatic disease in infants aged 0 to 6 months by 44%, and that vaccine effectiveness was 80% against laboratory-confirmed influenza-associated deaths among children aged 6 months to 17 years.²

“As physicians, we cannot overemphasize the importance of passive immunity for newborns when it comes to influenza, COVID-19, and RSV,” said lead influenza guidance author Kevin Ault, MD, FACOG.¹

“Maternal vaccination protects infants from serious illness and hospitalization in their first few months of life when they are unable to be vaccinated. Maternal flu vaccination after birth does provide antibodies through breast milk, but the infant does not get the full benefit of passive protection from vaccine-induced maternal antibodies that would have been transferred through the placenta.”

In a previous interview with Contemporary OB/GYN, Ault commented on the linking of vaccines to autism, as the subject has circulated again in recent years, despite decades of research that show no association.

“The data are very consistent that vaccines do not cause autism,” Ault said in February 2026, referencing multiple long-term follow-up studies evaluating children exposed in utero to influenza vaccines or pertussis-containing vaccines, including studies with 5 years of follow-up.^1,4

Coadministration of immunization vaccines in pregnancy

ACOG noted that all vaccines approved for use in pregnancy for COVID-19, RSV, and influenza can be administered simultaneously with no impact on efficacy, with the added benefit of increasing overall vaccine uptake.

“An ob-gyn remains one of the most trusted messengers for pregnant patients when it comes to vaccination,” said Clare. “And when the vaccines are available in the office at the time that the patient is being counseled, the odds of vaccine acceptance and receipt are 5- to 50-times higher. So, the opportunity is there to change our current trajectory and prevent the devastating consequences that come from not being protected.”¹

References:

1. American College of Obstetricians and Gynecologists. ACOG releases 2026-27 respiratory virus season immunization recommendations for pregnant and postpartum individuals. Press release. Published September 2, 2026.
2. Vaccine Integrity Project; CIDRAP, University of Minnesota. 2026-27 respiratory season evidence review. Published September 2, 2026. https://vaxintegrity.cidrap.umn.edu/2026-27-respiratory-season-evidence-review
3. Lipson RA, Senerth E, Watson MA, et al. COVID-19 Vaccine Effectiveness and Safety for the 2026-2027 Respiratory Season. JAMA. Published online September 02, 2026. doi:10.1001/jama.2026.18191
4. Autism and Vaccines: What the Science Really Says. National Foundation for Infectious Diseases. Updated April 18, 2025. Accessed September 2, 2026. https://www.nfid.org/autism-and-vaccines-what-the-science-really-says/