Pfizer vaccine effectiveness in pregnant women.

This was mostly for pre-Delta as the study ran from December 20th to June 3rd in Israel.

Estimated vaccine effectiveness was 96% against infection, 97% against symptomatic infection, 89% against hospitalization (wide CI:43-100% for hospitalization so interpret the point estimate with caution).

Only 1 event of severe disease in the unvaccinated group and 0 in the vaccinated group. 0 deaths in either group. So VE for severe disease/death could not be estimated and for hospitalization is quite wide. Also note pregnant women might be more likely to be hospitalized as a precautionary measure.

The CDC explicitly recommends pregnant women get vaccinated against the virus. The vaccine is safe and effective in this group. Pregnant women are at heightened risk of severe disease and death from the virus and there is a higher risk of preterm birth if infected.

Antibodies of vaccinated pregnant women pass through the placenta and breast milk. Women that get vaccinated after birth will also pass antibodies through their milk. We don't know the exact protection these antibodies confer the newborn at the moment.