Glucagon-Like Peptide 1 Receptor Agonists Use prior to Pregnancy Is Not Associated with Abnormal Birthweight

Introduction and Objective: Glucagon-like peptide-1 receptor agonists (GLP1 RAs) are contraindicated in pregnancy. The effects of pre-pregnancy GLP1 RA exposure on birthweight and other pregnancy outcomes is unknown. Methods: In a retrospective cohort of 130,844 pregnancies (2016 to 2024), we used prescription records from 3 years prior to conception to the end of the 1st trimester to identify 181 full-term, singleton pregnancies with pre-pregnancy exposure to GLP1 RAs. We applied propensity scores based on pre-pregnancy body mass index (BMI), maternal age, race/ethnicity, health insurance status, and year and location of delivery to match 1 GLP1 RA exposed to 3 unexposed pregnancies. We fit logistic mixed models to examine the risk of large for gestational age birthweight (LGA, birthweight >90th percentile for gestational age and sex) in exposed versus unexposed pregnancies. Secondary outcomes included small for gestational age birthweight (SGA) and gestational weight gain (GWG). We also examined birthweight outcomes after limiting the exposure window 6 months prior to conception through 1st trimester. Results: We included 724 pregnancies (181 exposed and 543 unexposed). Mean [SD] maternal age at delivery was 34.2 (5.0) years, mean [SD] pre-pregnancy BMI was 37.0 (8.4) kg/m2, and 17.9% of pregnancies had pre-existing diabetes. There was greater GWG in the GLP1 RA exposed group (29.4 [28.9, 35.2] versus 26.2 [24.8, 27.7] lbs). The odds of LGA and SGA were not different in the GLP1 RA exposed versus the unexposed group (LGA: 15% of exposed vs 18.2% of unexposed, OR 0.82 [0.52, 1.30], p=0.40; SGA: 6.6% of exposed and 6.8% of unexposed, OR 0.97 [0.48, 1.94], p=0.93). In 90 pregnancies exposed to GLP1 RA in the 6 months prior to conception and 270 unexposed pregnancies, the odds of LGA and SGA were also not significantly different. Conclusion: Despite greater GWG, the risk of LGA is similar among individuals exposed to GLP1 RA prior to pregnancy compared to unexposed matched controls. Disclosure: J. Maya: None. Y. Fu: None. D. Pant: None. T. Thaweethai: None. K. James: None. C.I. Batlle Camero: None. S. Hsu: None. D.C. Soria-Contreras: None. L. Shook: None. M. Hivert: None. C.E. Powe: Research Support; Dexcom, Inc. Other Relationship; Mediflix, Wolters Kluwer Health. Funding: American Diabetes Association (9-24-JDFWH-01); NIDDK K26DK138346 NIDDK T32DK007028MGH Physician/Scientist Development Award