Fast Five Quiz: COVID-19 Vaccines

Glenn Wortmann, MD


August 02, 2022

Data published in 2022 show that completing a two-dose primary mRNA COVID-19 vaccine series during pregnancy may help protect babies aged < 6 months from hospitalization due to COVID-19. A two-dose primary mRNA COVID-19 vaccination series during pregnancy was shown to be 61% effective against COVID-19 hospitalization among infants aged < 6 months, per Halasa and colleagues.

In a recent systemic review by Pratama and colleagues, antibody responses were stronger and associated with better transplacental antibody transfer after the addition of one mRNA booster, too. The Royal College of Obstetricians and Gynaecologists (United Kingdom); the American College of Obstetricians and Gynecologists (United States); the Society of Obstetrics and Gynecology of Canada; and the Royal Australian and New Zealand College of Obstetricians and Gynaecologists recommend that pregnant patients receive vaccination (first, second, and/or booster dose) at any time during pregnancy.

Vaccination during pregnancy has been shown to build antibodies that might protect the fetus. Antibodies made after a pregnant person received an mRNA COVID-19 vaccine are detected in umbilical cord blood after birth. A recent study by Shook and colleagues found that at 6 months old, 57% of infants born to pregnant people who were vaccinated during pregnancy had detectable antibodies against COVID-19, compared with 8% of infants born to pregnant people who had COVID-19 during pregnancy.

No adverse pregnancy-related outcomes occurred in clinical trials that used the same viral vector vaccine platform as JNJ-78436735 (Janssen Pharmaceuticals Companies of Johnson & Johnson). Vaccines that use the same viral vector have been given to people in all trimesters of pregnancy, including in a large-scale Ebola vaccination trial. No adverse pregnancy-related outcomes, including adverse outcomes affecting the baby, were associated with vaccination in these trials.

Currently, vaccination (two initial doses and one booster) is generally recommended in all individuals who are pregnant or who may become pregnant, including those who have had COVID-19. This population is at higher risk for severe COVID-19 compared with nonpregnant individuals of childbearing age, and COVID-19 is associated with an increased risk for preterm birth. The World Health Organization currently recommends that pregnant individuals may be vaccinated if the benefit of vaccinating outweighs the potential vaccine risks in that individual. The Centers for Disease Control and Prevention (CDC) recommends vaccination with any of the US Food and Drug Administration–approved vaccine options for all individuals who are breastfeeding, pregnant, or may become pregnant.

Learn more about COVID-19 vaccination while pregnant or lactating.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.