The Association of Overweight and Obesity with Menarche Age in Girls Aged 11-15 Years in Iran; A Cross-sectional Study.

Introduction: Epidemiologic studies have shown a discrepancy between overweight and puberty processes. This cross-sectional study was aimed to clarify these associations in the Iranian girl population. Methods: A total of 1300 girls aged 11-15 years were randomly selected from Mashhad, in the northeast of Iran, using a multi-stage cluster sampling method. The demographic data were collected and weight, height, and waist circumference (WC) were measured, then Body Mass Index (BMI) and Waist-to-Hip ratio were calculated. Overweight and obesity were defined based on WHO reference data. Central obesity was defined as ≥90th percentile of WC. Linear regression and unconditional binary logistic regression were performed to investigate the association between socio- demographic parameters and age at menarche in months, puberty categories, and menarche age groups (<12 vs. ≥12 years) respectively. Results: The prevalence of overweight, obesity, and abdominal fat distribution were 11.5%, 10.3%, and 10.5% respectively. Menarche was experienced by 63% of subjects at the mean age of 12.24±0.98 years. Regression tests revealed that the odds of menarche occurrence at the age of 12 or more was significantly lower in girls with higher BMI (OR: 0.31, 95%CI: 0.22-0.43) than their leaner counterparts (P< 0.001). Conclusion: The findings suggest that being overweight or obese is a possible predictor of experiencing menarche at a younger age. [ABSTRACT FROM AUTHOR]