19/04/2021
Encouraging Findings About SARS-CoV-2 mRNA Vaccination During Pregnancy
Gray KJ et al. Am J Obstet Gynecol 2021 Mar 24
In pregnant and lactating persons, vaccine side effects and immune responses were similar to those in nonpregnant persons.
The clinical trials leading to the rollout of COVID-19 vaccines excluded pregnant women, despite large numbers of childbearing women in healthcare who were in the highest priority level for initial immunization in December 2020. To address this gap, a cohort of 84 pregnant, 31 lactating, and 16 nonpregnant women was studied throughout the course of receiving the Pfizer or Moderna mRNA vaccines.
Antibody titers following each vaccine dose were similar in pregnant, lactating, and nonpregnant women. Antibodies were transferred into breastmilk and cord blood, with titers rising with time after the boost. Immunoglobulin A (IgA) was noted following the initial immunization but was not boosted by the second vaccination. Side effects were consistent with known reactogenicity of these vaccines, with 32% of pregnant and 43% of lactating women reporting fever after the second dose.
COMMENT
In providing initial data on the immunologic responses to SARS-CoV-2 mRNA vaccines in pregnant and lactating persons, this study can be utilized by clinicians to encourage hesitant pregnant women to receive the vaccine. Optimal vaccine timing during pregnancy as well as neonatal protection require further study. The lack of these essential data when the vaccines were first rolled out has triggered stronger calls for including pregnant women in pivotal clinical trials.