Background: A secular trend towards earlier menarche has been observed.
Objective and hypotheses: The correlation of age at menarche with the BMI as well as the maternal age at menarche and their BMI.
Method: This is a cross-sectional study conducted from October 2012December 2013. A pre-selected, representative elementary and high school cohort was derived, using stratification and PPS methodology. Parents responded to questionnaire and students were measured with high sensitivity methods. IOTF cut offs were used. Data were analysed for 12 986 mothers and for 2 272 adolescents for which age at menarche was available. All the variables used are binary (binomial, dichotomous) in nature. The menarche age of the subject and her mother is Normal vs Early (<12 years).
Results: Analysing the whole group early menarche had 27.5% of the girls as compared to 15.0% for the mothers (OR=2.1 95% CI=1.92.4). For the sample of 2 272 girls with known age at menarche for the girl and the mother, early menarche had 32.9% of the girls and 17.7% of the mothers (OR=2.395% CI=2.02.6). The correlation coefficient between the mothers and the daughters age at menarche equal to 0.375 (P<0.01).The percentage with early menarche was 28.8% for normal weight girls and 43.1% for overweight/obese girls (OR=1.9, 95% CI=1.62.3). Early menarche had 61.0% of the girls whose mother had early menarche as compared to 26.9% of the girls whose mother had normal menarche (OR=4.395% CI=3.45.3). In both generations the OR of the association between age at menarche and BMI is of the same order.
Conclusion: The most significant association is the effect of the mothers age at menarche to the daughters age at menarche. This generation has early menarche in higher proportion than their mothers. BMI is positively correlated with mothers BMI and negatively associated with age at menarche.
Funding: This work was supported by an EU grant MIS301205.
01 - 03 Oct 2015
European Society for Paediatric Endocrinology