Early Menstrual Factors Are Associated with Adulthood Cardio-Metabolic Health in a Survey of Mexican Teachers.

Objectives To evaluate whether age at menarche and time to menstrual regularity were related to cardio-metabolic risk factors in Mexican women. Methods The study population comprised 54,921 women from the 2008-2010 wave of the Mexican Teacher's Cohort. A modified Poisson approach was used; exposures were age at menarche and time to menstrual regularity (< 1 year vs. ≥1 year), and outcomes were prevalent obesity, type 2 diabetes, high blood pressure, and high cholesterol. Results Mean (SD) age of women was 42.1 (7.6) years, and mean (SD) menarcheal age was 12.5 (1.5) years. Compared to women with menarche age 13 years, those with menarche < 9 years had a 65% (95% CI 43-90%); 27% (95% CI 4-55%); and 23% (95% CI 1-49%) higher prevalence of obesity, high blood pressure, and high cholesterol, respectively. For diabetes, there was a U-shaped association; compared to menarche age 13 years, those with menarche < 9 years had an 89% higher prevalence of diabetes (95% CI 39-156%), and those with menarche ≥ 17 years had a 65% higher prevalence (95% CI 16-134%). Among women with regular cycles (n = 43,113), a longer time to menstrual regularity was associated with diabetes (PR = 1.11 with 95% CI 1.02-1.22), high blood pressure (PR = 1.11 with 95% CI 1.06-1.17), and high cholesterol (PR = 1.09 with 95% CI 1.04-1.14). Conclusions for practice Mexican women with earlier and later ages at menarche and/or longer time to menstrual regularity may have higher risk of cardio-metabolic disease in adulthood.