Gestational weight gain and daughter's age at menarche.

Background: Sexual development begins in utero and enters a dormant phase during infancy. The influence of maternal gestational weight gain (GWG) on daughter's age at menarche has not been explored.

Methods: We investigated the association between maternal GWG and age at menarche (<11 years, 11-15 years, >15 years of age) in a large cohort study of U.S. nurses, The Nurses' Health Study II (NHS II), and the Nurses' Mothers' Cohort Study.

Results: Among 32,218 respondents, 7% reported age at menarche age 15. Compared with women whose mothers gained 20-29 lbs during pregnancy, those whose mothers reported <10 lbs or >40 lbs of GWG were 30% more likely to report early onset menarche (<11 years of age) in logistic regression models adjusted for sociodemographic and maternal characteristics, and childhood body size and physical activity: adjusted odds ratio (OR) 1.31, 95% confidence interval (CI) 1.05-1.62, and 1.27, 95% CI 1.06-1.56. Maternal GWG was not associated with late menarche in the fully adjusted model (p(trend)=0.07).

Conclusions: These results suggest that either extreme of maternal GWG may influence risk for early age at menarche in daughters. Maternal GWG may be a modifiable risk factor for early menarche.