COVID vaccine protects moms and babies

The Pfizer mRNA vaccine is safe and effective against SARS-CoV-2 during pregnancy— providing protection to both mother and newborn child—according to a Weizmann Institute study. Prof. Michal Neeman, from the Department of Biological Regulation, worked with scientific and clinical colleagues on campus and in medical centers around the country to address an urgent question in COVID-19 care: whether or not pregnant women should receive the vaccine. The study was done in collaboration with Prof. Michal Kovo from Edith Wolfson Medical Center and Prof. Simcha Yagel from Hadassah University Medical Center.

Pregnant women who contract COVID-19 have a higher risk of severe complications and death compared to non-infected pregnant women. The significant risks posed by COVID-19 in pregnancy have sparked a worldwide debate regarding prenatal SARS-CoV-2 inoculation, given the lack of sufficient evidence regarding vaccine effectiveness in pregnant women and newborns. Pregnancy is usually an exclusion criterion for vaccination studies and most other clinical trials; during a pandemic, that exercise of caution can be deadly.

“Among the many things this pandemic has taught us, is the potential harms caused by current directives excluding pregnant women from clinical trials,” says Prof. Neeman. “We need to re-evaluate these policies.”

Prof. Neeman and her colleagues examined blood samples from women and cord blood from neonates following childbirth. In this way, the scientists were able to obtain substantial evidence for the effect of vaccination versus regular infection on maternal immunity. They were also able to see whether the immune response passes from mother to fetus via the placenta, which would indicate that, potentially, immune protection extends to newborns. 

The scientists found that both vaccinated women and women previously infected with SARS-CoV-2 generated and transferred protective antibodies across the placenta to their unborn children—providing clear evidence of the value of vaccination in pregnancy. Moreover, the findings indicate that protection against infection extends to the neonate, outlining benefits for both maternal and child health. 

“Our study has immediate health implications for women around the world. Unvaccinated pregnant women continue to contract the virus, with devastating consequences, even here in Israel,” says Prof. Neeman. “It’s time to get the word out.”

—Anne Sperling

Prof. Michal Neeman is supported by the Helen and Morris Mauerberger Professorial Chair in Biological Sciences, the Benoziyo Endowment Fund for the Advancement of Science, the Henry Chanoch Krenter Institute for Biomedical Imaging and Genomics and Fondazione Henry Krenter, the Sagol Institute for Longevity Research, the David and Fela Shapell Family Institute for Preclinical Studies, and the Wolfson Family Charitable Trust & Wolfson Foundation.