Age at Menarche, Menstrual Characteristics, and Risk of Preeclampsia

We examined associations of age at menarche and menstrual characteristics with the risk of preeclampsia among participants (?=3,365) of a pregnancy cohort study. Data were collected using in-person interviews and medical record abstraction. Logistic regression was used to estimate adjusted odds ratio (OR) and 95% confidence interval (95% CI). There was a significant inverse association between age at menarche and risk of preeclampsia (? value for trend 36 days) with higher risk of preeclampsia was present only among women who had prepregnancy body mass index <25 kg/m2 (interaction ? value = 0.04). Early menarche is associated with higher risk of preeclampsia. Prepregnancy weight may modify associations of long menstrual cycles with risk of preeclampsia.