Body size at birth, early-life growth and the timing of the menopausal transition and natural menopause

Background Whether birth weight and early-life growth are associated with age at menopause has not been resolved. Methods We conducted a prospective study in two U.S. birth cohorts to investigate the relation of weight at birth and weight and growth trajectory through age 4 years to menstrual status among 1001 women ages 39–49 years. We used logistic regression models with GEE. Results Women who weighed more at birth and at one year were less likely to have experienced the menopausal transition or natural menopause by age 39–49 years (odds ratio(OR) = 0.50, 95% confidence interval(CI) = 0.32, 0.77 and OR = 0.82, 95%CI = 0.68, 0.99 per kilogram increase at birth and age one, respectively). Conclusions Women who had a lighter weight at birth and women who were lighter than their peers through infancy experienced the menopausal transition or natural menopause at an earlier age.