The full two-dose regimen of Pfizer’s COVID-19 vaccine was 78 percent effective in preventing infection among pregnant women, according to a real-world Israeli study published July 12 in JAMA.

Researchers analyzed data on 7,530 pregnant women who received their first dose of Pfizer’s vaccine between Dec. 19 and Feb. 28 in Israel. The women were matched in a 1:1 ratio with 7,530 unvaccinated pregnant women by the following factors: age, gestational age, residential area, population subgroup, number of times they had given birth and flu vaccination status (which was used to indicate health-seeking behavior). They were observed until April 11.

The average age among all participants was 31.1.

Of the vaccinated women, 118 (1.6 percent) were infected with COVID-19 at least 28 days after receiving their first dose, compared to 202 (2.7 percent) of unvaccinated women.