Researchers have found that while the benefits of COVID-19 vaccination during pregnancy have waned over time, they remain substantial for public health, publishing their findings in JAMA Network Open.1
Pregnancy was removed as an indication for COVID-19 vaccination in May 2025 by the US Department of Health and Human Services. However, data has highlighted the transfer of maternal antibodies to the infant when vaccination is provided during pregnancy, offering direct protection to newborns during a period where the risk of severe infection is greater.
Key takeaways:
- Study findings published in JAMA Network Open show that COVID-19 vaccination during pregnancy continues to provide meaningful protection for both mothers and infants.
- Maternal antibodies transferred during pregnancy help shield newborns under 6 months, who face a higher risk of severe COVID-19 infection.
- Modeling data from 2024 to 2025 estimated over 1,200 infant and 200 maternal hospitalizations could be prevented with 50% vaccination coverage.
- Effectiveness has declined over time, but researchers stress vaccination still significantly reduces COVID-19 hospitalizations in this population.
- Experts urge reconsideration of vaccine eligibility during pregnancy and highlight the broader importance of maternal immunization for COVID-19, influenza, and RSV.
“Infants younger than 6 months are not eligible for COVID-19 vaccination, and their risk of severe COVID-19 is much higher than other pediatric age groups, often similar to those aged 65 to 74 years in the current epidemiologic era,” wrote investigators.
Assessing avoidable COVID-19 hospitalizations
The study was conducted to identify the number of preventable COVID-19 hospitalizations in pregnant patients and their young offspring through vaccination during pregnancy. COVID-19 hospitalizations between January 2024 and May 2025 were identified through publicly available US surveillance data. Patients were aged 18 to 49 years.
Most COVID-19 vaccines during pregnancy were administered during the second or third trimester. The impact of this regimen on health outcomes was assessed using recent vaccine effectiveness estimates, such as an estimated 35% decline in COVID-19 hospitalization risk in infants aged under 6 months and 33% effectiveness across 4 months in adults.
There were 7148 estimated cases of COVID-19 hospitalization in young infants among a population of 1.83 million between January 2025 and May 2025. Among pregnant patients, 3106 COVID-19 hospitalizations among a population of 3 million were estimated.
Hospitalization estimates and vaccine impact
COVID-19 hospitalization was estimated to be averted in 1251 infants when vaccine coverage was 50%, vs 2502 when coverage was 100%. In pregnant patients, 228 severe COVID-19 cases were averted at 50% coverage vs 456 at 100%. When vaccine coverage was low:
- 375 hospitalizations were averted in infants
- 68 severe cases were averted in pregnant patients
These results indicated significant benefits from COVID-19 vaccination during pregnancy. While these benefits have waned over time, investigators concluded the data highlight a need to reconsider removing vaccine eligibility during pregnancy.
“Continued studies on the COVID-19 risk and vaccine effectiveness in this population are important,” wrote investigators.
Maternal vaccination remains critical
The importance of maternal vaccination has been highlighted by Robert H. Hopkins, Jr, MD, Medical Director for the National Foundation for Infectious Diseases, in an interview with Contemporary OB/GYN.2During the discussion, Hopkins highlighted how pregnancy is a risk factor for severe illness, with vaccination reducing both maternal and infant risks.
These protective effects extend beyond COVID-19 vaccination, with influenza and RSV vaccination also vital for protecting mothers and their offspring. While these diseases are not often severe in pregnant women, transfer of antibodies to the infant can prevent potential severe infections in this vulnerable population.
Hopkins recommended that clinicians approach the topic of vaccination with their patients by discussing health goals and addressing patient concerns. Vaccines should be recommended to pregnant women to provide equal protection to themselves and their infants.
“I think all of us are in this together,” said Hopkins. “You know, we're focusing on the ob-gyn provider. But I think it's also important that we think about these women in their medical home that they may follow with on a on a regular basis, the primary care community, medical staff within that home as well as in their ob-gyn offices.”
References
- Lo NC, Maldonado Y, Chu HY, Hotez PJ, Kiang MV. Modeling the health impact of discontinuing COVID-19 vaccination during pregnancy in the US. JAMA Pediatr. 2025. doi:10.1001/jamapediatrics.2025.3561
- Krewson C. The importance of maternal vaccination. Contemporary OB/GYN. November 13, 2023. Accessed October 9, 2025. https://www.contemporaryobgyn.net/view/the-importance-of-maternal-vaccination.
