mRNA Vaccination Protects Pregnant Women

During pregnancy, hormonal levels and immune system function may increase women's vulnerability to viral infections, says the U.S. CDC. Although a SARS-CoV-2 coronavirus infection in pregnant women has been reported mostly asymptomatic or mild, it may result in severe complications.

In an observational, retrospective cohort study of Israeli pregnant women published in the JAMA on Jul 12, 2021, the BioNTech - Pfizer (Comirnaty, BNT162b2) vaccine was associated with a significantly lower risk of SARS-CoV-2 infection compared with no vaccination.

This study' cohort included 7,530 vaccinated and matched unvaccinated women, 46% and 33% in the second and third trimester, respectively, with a mean age of 31.1 years. The median follow-up for the primary outcome was 37 days.

These researchers found 118 SARS-CoV-2 infections in the vaccinated group and 202 in the unvaccinated group.

Among infected women, (83.8%) were symptomatic in the vaccinated group vs. (83.2%) in the unvaccinated group.

Furthermore, during 28 to 70 days of follow-up, there were 10 infections in the vaccinated group and 46 in the unvaccinated group.

The hazards of infection were 0.33% vs. 1.64% in the vaccinated and unvaccinated groups, respectively, representing an absolute difference of 1.31% (95% CI, 0.89%-1.74%), with an adjusted hazard ratio of 0.22 (95% CI, 0.11-0.43).

Moreover, this study reported vaccine-related adverse events were reported by 68 patients; none was severe.

The researchers concluded by saying, 'Interpretation of study findings is limited by the observational design.'

Note: Maccabi Healthcare Services established and maintenance of computerized pregnancy and COVID-19 registries. Their assistance was provided as part of their work in the health fund. No one received any additional compensation beyond the usual salary for their contributions. No conflicts were disclosed.