Age at menarche, menstrual cycle characteristics and risk of gestational diabetes

Aims: We examined associations of age at menarche and menstrual cycle characteristics with gestational diabetes mellitus (GDM) risk. Methods: Study participants (N = 3490) recruited prior to 16 weeks of gestation were followed until delivery. Menstrual history data were collected using questionnaires. GDM was diagnosed using the American Diabetes Association 2003 guidelines. Logistic regression was used to estimate odds-ratios (OR) and 95% confidence intervals (CI). Results: Age at menarche was not associated with GDM risk. Women who had long menstrual cycles (>36 days) had higher risk of GDM compared with women who had normal cycle length (25-30 days) (OR = 1.6; 95% CI0.98-2.67). Women who had long menstrual cycles and were either overweight or gained >5 kg in adulthood had 4-5-fold higher GDM risk compared with women who had normal cycle length and were non-obese or gained <5 kg in adulthood, respectively (OR = 4.03; 95% CI:2.08-7.81 and OR = 4.62, 95% CI:2.65-8.07, respectively). Conclusion: Longer menstrual cycles are significantly associated with increased risk of GDM, particularly among women who were either overweight or obese pre-pregnancy, or had >= 5 kg weight gain in adult hood. Menstrual history may help identify women with increased risk of GDM. (C) 2011 Elsevier Ireland Ltd. All rights reserved.