Prevalência e fatores associados à menarca precoce em adolescentes da coorte RPS em são luís do Maranhão.

Abstract

Menarche is the name given to the first menstrual cycle and occurs between 12 and 13 years of age. The age of its occurrence is influenced by genetic, environmental, social, and body composition aspects. Menarche is called precocious when this first menstrual cycle occurs before the age of 12 years. The aim of this study is to analyze the prevalence and factors associated with early menarche in adolescents, from the third follow-up of the 1997/98 cohort in São Luís, which took place in 2016. This is a cross-sectional study, nested within a cohort study. The sample included female adolescents between 18 and 19 years of age, with a valid report of age at menarche and with body composition tests and anthropometric measurements, totaling 1,294 adolescents. Menarche was considered an outcome variable. The exposure variables used were: socioeconomic characteristics of the adolescents and their parents, reproductive health, life habits and body composition. Factors associated with early menarche were obtained using Poisson regression with robust variance and a hierarchical approach. The variables were placed in three distinct blocks: sociodemographic characteristics (distal), lifestyle (intermediate) and body composition (proximal). In each block, the variables present were adjusted among themselves and those with a p value < 0,10 remained for the next block. Factors associated with early menarche were considered as variables with a p- The regression results were expressed in prevalence ratios (PR) and their respective 95% confidence intervals. The prevalence of early menarche was 32.3%, among the adolescents who had early menarche, brown/mulatto/brunette/caboclo skin color was the majority (62.3%), 68.4% studied and 87.0% did not work. It was observed that the highest percentage of adolescents belonged to socioeconomic classes B and C (46.11% and 45.21%) and had a high percentage of body fat (72.02%). In the multiple Poisson regression with a hierarchical approach, for the categories of variable black/black skin color RP 0.60 (95% CI 0.44 - 0.80 and p value=0.001), the color brown/mulata/caboclo/ brunette PR 0.79 (95%CI 0.64 - 0.96 and p value=0.017) and the overweight category with PR 1.20 (95%CI 0.98 - 1.47 and p value =0.082) were associated with early menarche. Conclusion: Adolescents with black or brown skin color were less likely to have early menarche and more likely to be overweight.