Available Evidence Limited but Does Not Suggest Major Adverse Outcomes with Early GLP-1 Use in Pregnancy

A target trial emulation estimated the risks associated with glucagon-like peptide-1 receptor agonist (GLP-1RA) exposure in early pregnancy. The findings did not indicate substantially increased risk for nonlive birth, abnormal fetal growth, or major congenital malformation with continuation of GLP-1RAs into the first trimester. As GLP-1RA use among women of reproductive age becomes more prevalent, the findings can provide some reassurance for pregnant women with unintentional first-trimester exposure to GLP-1RAs. The study is published in Annals of Internal Medicine. 

Researchers from Harvard T.H. Chan School of Public Health and colleagues analyzed insurance claims data from 3,572 pregnancies between 2011 and 2024, comparing continuation of GLP-1RAs into the first trimester (≥ 1 further dispensation after conception) relative to non-continuation. The findings showed similar risks between the two treatment regimens for most outcomes, with no definitive increase apparent for continued medication use. However, because estimates were imprecise, particularly for rarer outcomes of major congenital malformation and small size for gestational age at birth, the authors conclude that further research would be valuable to better understand safety of GLP1-RAs in pregnancy.