Age at Menarche and Related Factors in Girls of Urban Areas of Markazi (Central) Province of Iran

The age at menarche is an indicator of racial, geographical and nutritional patterns of different societies. This cross-sectional study conducted on 1223 girls aged 14-20 in the Markazi (Central) Province, Iran in 2010. In this research, the age at menarche, as the main variable, was determined for each city and compared between different cities. The statistical analyses included c2 test for determining statistically significant differences, variance analysis for determining the difference between groups, and Pearson correlation coefficient for determining the relationship between variables. The average age of first menstruation was 13.21 +/- 1.33 years in the Markazi Province, with no significant difference among the cities of the province. This age is inversely related to body mass index (BMI), nutritional status and weight. The pattern of distribution of BM I is similar for all the cities in the province. Although, the average age at menarche in the Markazi (central) Province, a cold area, is higher compared to warmer regions in Iran, it may be more influenced by race than by the climate. Considering the lower age at menarche in Markazi Province compared to previous similar studies, it may be stated that social well-being and nutritional standards have improved in the province.