Excess weight as a promoting factor of menarche: A study of secular trend in girls from La Plata city (Buenos Aires, Argentina)

TORRES MF; GARRAZA M; BERGEL SANCHÍS ML; LUNA ME; QUINTERO FA; NAVAZO B; CESANI MF

Denver

Congreso; 47th Annual Meeting of the Human Biology Association; 2022

Human Biology Association

The age at menarche (AgM) has decreased over the lastcentury according to the literature. Although the reasonsare not completely known, one possible explanationrelates to the childhood obesogenic environment, sincethe gene pool remains “relatively” stable over time. Theaim of this study was to compare prevalence of menarche(M) and AgM in two cohorts from La Plata city and evaluate whether they differ from each other and in relationto the presence of excess weight (EW). Both cohorts(C) come from cross-sectional studies: C1 (years:2005-2007; N=418) and C2 (years: 2014-2017; N=474)conducted with the same methodological samplingcriteria (8-14 years old and schools). Presence (MP)/absence (MA) of menarche was recorded, prevalencewere calculated and compared by Chi2 test. According tostatus quo method and logistic regression analysis, AgMwas estimated and compared between cohorts. Likewise,BMI was calculated from weight (kg) and height(cm) and standardized to Z-scores (WHO) to estimateprevalence of EW (BMI>1Z) by cohort and maturitystage. The results indicated that MP (25.1%) was higherin C2 than in C1 (28.7% vs 21.1%); that AgM was higherin C1 than in C2 (12.21 years vs 12.82 years) and that EW(30.3%) was greater in C2 than in C1 in both MA (18.4%vs 10.6%) and MP (19.6% vs 14.3%). In a context markedby a significant increase in excess weight, menarcheexhibits a positive secular trend, both in prevalence andage of occurrence, showing a decrease of 7 months in thedecade analyzed.