Idade da menarca em escolares de uma comunidade rural do Sudeste do Brasil

Abstract

The purpose of this study was to determine the 3rd percentile (P3), 50th percentile (P50 = median age at menarche = MAM), and amplitude between the extremes (P97 and P3) of age at menarche among schoolgirls in the county of Barrinha, São Paulo, Brazil. Values were correlated with socioeconomic conditions such as social class, number of siblings, and father's employment status. This was a cross-sectional study based on the use of status quo adjusted by logit for calculation of percentiles. A questionnaire was applied to 1,602 schoolgirls aged 8 to 17 years (incomplete). MAM was 12 years (y) and 6 months (m), with a P97 of 10 y and 2 m and a P3 of 14 y and 10 m. Girls from lower-income families and those with unemployed fathers showed later MAM. No difference in MAM was observed with respect to number of siblings. Amplitude between P97 ad P3 was great in the overall sample. We conclude that Barrinha presented a MAM similar to and even lower than regional values for Brazil and for some developed countries. The study of the interval between extreme percentiles proved to be a better indicator of biological diversity and socioeconomic inequality than MAM alone.

Indicadores de aptidão física de escolares da região centro-oeste da cidade de São Paulo

“…A estabilização de desempenho no sexo feminino após os 11 anos foi verificada em outros estudos brasileiros 5,[20][21][22][23][24] . A partir dos 10-11 anos de idade, é cada vez maior o número de meninas que já apresentaram a menarca 25,26 , e este fato tem importante interferência nos índices de aptidão física feminina. A menarca é diretamente associada ao surgimento de características sexuais do corpo feminino adulto, destacando-se um aumento no percentual de gordura corporal.…”

Socioeconomic status and age at menarche in indigenous and non-indigenous Chilean adolescents

“…According to previous studies, among girls from lower socioeconomic strata, menarche is delayed by exposure to adverse environmental and nutritional factors during early childhood or even deficient nutrition during adolescence 5,6,7,8,9 . However, other studies indicate that among lower socioeconomic strata, menarche may occur earlier because rates of obesity and overweight are higher in such groups 10,11 .…”

Resiliência e apoio social de mães adolescentes em vulnerabilidade social

“…Estudos indicam que a menarca ocorre mais precocemente em zonas urbanas (Picanço,1995) e em famílias com maior renda (Tavares et al, 2000;Picanço,1995).…”

“…Outros estudos também correlacionam a antecipação da idade da menarca com fatores genéticos (Ong KK et al, 2011), ausência do pai (Deardorff et al, 2011), número inferior a dois irmãos (Picanço, 1995) e desemprego dos pais (Tavares et al, 2000).…”