COVID-19 boosters are not linked to an increased chance of miscarriage, according to a new study in JAMA Network Open.
Researchers were seeking to learn whether a booster in early pregnancy, before 20 weeks, was associated with greater likelihood of spontaneous abortion.
They examined more than 100,000 pregnancies at 6-19 weeks from eight health systems in the Vaccine Safety Datalink (VSD). They found that receiving a COVID-19 booster shot in a 28-day or 42-day exposure window did not increase the chances of miscarriage.
The VSD is a collaboration between the Centers for Disease Control and Prevention’s Immunization Safety Office and large health care systems. The “observational, case-control, surveillance study” was conducted from Nov. 1, 2021, to June 12, 2022.
“COVID infection during pregnancy increases risk of poor outcomes, yet many people who are pregnant or thinking about getting pregnant are hesitant to get a booster dose because of questions about safety,” said Elyse Kharbanda, MD, senior investigator at HealthPartners Institute and lead author of the study in a press release.
The University of Minnesota reported that “previous studies have shown COIVD-19 primary vaccination is safe in pregnancy and not associated with an increased risk for miscarriage. Several studies have also shown COVID-19 can be more severe in pregnancy and lead to worse outcomes for the mother.”
The study was funded by the CDC. Five study authors reported conflicts of interest with Pfizer, Merck, GlaxoSmithKline, AbbVie, and Sanofi Pasteur.
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