Factors contributing to early menarche in school girls.

Objective: To assess the average age of menarche in Pakistani girls from different socioeconomic backgrounds.

Methodology: This was a cross sectional study design carried out on female students studying in different schools of Karachi in 2014. Girls aged 10-14 years age were included. Schools from all three socio economic strata were selected through random sampling technique from a list of schools having health care services. Data was collected through a self-administered questionnaire translated in Urdu where required. Height and Weight was measured through calibrated instruments. Sample size was n=385 based on maximum proportion of 50%. Analysis was done on SPSS version 20. Chi-square and ANOVA was applied after checking data for normality.

Results: The total sample size was 275 after excluding poorly filled questionnaires. The mean age of menarche in our sample population was 11.73±1.2 years. Out of the total participants 127 (46%) students had reached the age of menarche. It was found that mean age of menarche was highest in participants of Kashmiri origin 14.5±0.1 years and lowest mean age was observed in those of Gujrati origin at 11.0±0.1 years (p 0.036). When mean age of menarche was compared with socioeconomic class highest mean age was observed in lower class 12.13 ±0.1 (p 0.268).

Conclusions: Our study reveals a decline in the mean age of menarche of at least 2 years in girls aged 10-14 years.