Reproductive lifespan in relation to diabetes mellitus and metabolic syndrome in a nationally representative population

Abstract

Abstract Aims The association between reproductive lifespan (RLS) and diabetes and metabolic syndrome in menopausal women remains unclear. We investigated whether a short RLS is associated with diabetes and metabolic syndrome using nationally representative US data. Methods We conducted a cross-sectional analysis of menopausal women using data from the US National Health and Nutrition Examination Survey from 2007 to 2018. Weighted logistic regression models accounting for the complex survey design were used to estimate ORs and 95% CIs for diabetes and metabolic syndrome across quartiles of RLS. Results A total of 868 postmenopausal women with a mean age of 54.1 years were included. The mean ages at menarche and menopause were 12.7 and 51.2 years, respectively. The mean RLS was 38.5 years and was categorized into quartiles (11–35, 36–39, 40–42 (reference group), and 43–50 years). Compared with the reference group, women in the second quartile had higher odds of diabetes (OR 2.23; 95% CI 1.05 to 4.73) after adjustment for age, demographic characteristics, behavioral factors, age at menarche, and family history of diabetes. In contrast, women in the shortest RLS quartile were not at increased odds of diabetes, and no significant linear trend was observed across RLS categories. No robust association was observed between RLS and metabolic syndrome. These findings were consistent in sensitivity analyses that additionally included women with surgical menopause and that further adjusted for dietary factors. Conclusion A relatively short RLS may be associated with higher odds of diabetes, although this association did not follow a clear dose-response pattern. These findings suggest that reduced lifetime estrogen exposure may contribute to cardiometabolic risk. Given the cross-sectional design, longitudinal studies are needed to support these findings.