Ann Intern Med

More evidence that metformin is safe in early pregnancy

June 21, 2024

Compared with switching to insulin monotherapy, maintaining metformin use and adding insulin during early pregnancy didn't significantly increase the risk of nonlive births for women who were already on metformin before pregnancy.

• In this observational cohort of pregnant women with pregestational T2DM using metformin monotherapy prior to their last menstrual period, a target trial with 2 treatment strategies was emulated: insulin monotherapy (n=850) or insulin plus metformin (n=1,557).
• Estimated risk for nonlive birth was 32.7% with insulin monotherapy (reference) vs. 34.3% with insulin plus metformin. Estimated risk for live birth with congenital malformations was 8.0% with insulin monotherapy vs. 5.7% with insulin plus metformin.

Source:

Chiu YH, et al. (2024, June 18). Ann Intern Med. Metformin Use in the First Trimester of Pregnancy and Risk for Nonlive Birth and Congenital Malformations: Emulating a Target Trial Using Real-World Data. https://pubmed.ncbi.nlm.nih.gov/38885505/