Pharmacologic sex hormones in pregnancy in relation to offspring obesity

OBJECTIVE: To assess the association between in utero exposure to either diethylstilbestrol (DES) or an oral contraceptive in pregnancy and offspring obesity. DESIGN AND METHODS: Using data from the Collaborative Perinatal Project (1959–1974), a multicenter prospective study of pregnant women and their offspring, we examined overweight or obesity among 34,419 children with height and weight data at age 7 years. We used generalized linear models to estimate the adjusted odds ratio (aOR) for overweight or obesity (≥85(th) percentile) or obesity (≥95(th) percentile) in the offspring according to exposure during different months of pregnancy. RESULTS: Oral contraceptive use during pregnancy was positively associated with offspring overweight or obesity and obesity. The magnitude of association was strongest in the first 2 months of pregnancy for obesity (aOR 2.0, 95% CI: 1.1, 3.7). DES use was also associated with offspring overweight or obesity and obesity, with the association being strongest for exposure beginning between months 3–5 (e.g., for exposure beginning in months 3–4, the aOR for obesity was 2.8, 95% CI: 1.3, 6.3). CONCLUSIONS: Pharmacologic sex hormone use in pregnancy may be associated with childhood obesity. Whether contemporary, lower-dose oral contraceptive formulations are similarly associated with increased risk of childhood obesity is unclear.