Objectives To determine the current prevalence and mean ages of onset of pubertal characteristics in healthy urban Chinese girls. Methods A cross-sectional study of sexual maturation of healthy Chinese girls was conducted in 9 representative cities of the eastern, western, southern, and northern parts and central region of China between 2003 and 2005. At examination, stages of breast and pubic hair development were rated on girls 3 through 19.83 years of age, and height and weight were also recorded. Data on menses were collected by the status quo method. Probit analysis was used to calculate the median age and 95% confidence interval (CI) for onset of breast and pubic hair development and menarche. Results Data were analyzed for 20654 apparently healthy girls. At age 8 years, 19.57% of these girls had evidence of breast development. The median ages of onset of Tanner stages 2 and 3 for breast development were 9.20 (95% CI: 9.06-9.32) years and 10.37 (95% CI: 10.28-10.45) years, respectively. The median ages of onset of Tanner stages 2 and 3 for pubic hair development were 11.16 (95% CI: 11.03-11.29) years and 12.40 (95% CI: 12.25-12.55) years, respectively. Menses occurred at 12.27 years (95% CI: 12.16-12.39). Conclusions These data suggest that urban Chinese girls are actually experiencing earlier breast development than currently used norms. The up-to-date reference for normal pubertal development in urban Chinese girls needs to be established for the purpose of determining precocious puberty or pubertal delay.

Onset of breast and pubic hair development and menses in urban chinese girls.

Effects of different socioeconomic conditions on menarche in Turkish female students.

Background Menarche is one of the most important biologic signals in the life of a woman. Menarche is a biological variable which has a significant genotypic component in girls. In recent years, many studies reporting the earlier onset of menarche owing to the improvement of socio-economic conditions have been published.



Design  We asked some questions about menarche to 1017 female students studying in the high schools of Manisa region in order to determine the menarcheal age and the correlation of menarcheal age between the mothers and daughters in our region.



Results  The mean age at menarche for the girls was 12.82 ± 1.07 years and for the mothers was 13.6 ± 1.39 years. The mean menarcheal age of the mothers was higher than the mean menarcheal age of the girls (P   25 (r = 0.04, P = 0.813). In girls with BMI < 25, there was a correlation between the menarcheal age of the girls and mothers (r = 0.282, P < 0.001).



Conclusion  These results suggest that the menarche occurs earlier in the daughters than their mothers. The correlation between the menarcheal age of the girls and their mothers persists under all circumstances except in obesity. The mother's menarcheal age is a good predictor of the daughter's menarcheal age in non-obese girls and the BMI is an important factor.

The factors affecting the relation between the menarcheal age of mother and daughter.

Menarche is an important milestone in the development of female adolescents. The study assessed the age at menarche using recall, its seasonality, and association with marital and nutritional status (using mid-upper arm circumference [MUAC]) among 3,923 female adolescents aged 12-19 years in a rural area of Bangladesh. At the time of assessment, most (88%) adolescents had attained menarche at the mean (standard deviation [SD]) age of 12.8 (1.4) years. Age of onset of menarche among married adolescents (13%) occurred earlier than in those who were unmarried (12.6 +/- 1.3 years vs 12.9 +/- 1.4 years, p < 0.01). Age at menarche was negatively associated with MUAC after adjusting for age and marital status (beta = -0.10, p < 0.01). More than 50% of the adolescents had an onset of menarche during winter (chi2 = 634.97; p < 0.001), with peaks in December and January. In this rural population, the current age at menarche was found to be slightly lower than the previous estimates of 13.0 years in Bangladesh. An early onset of menarche was associated with season and better nutritional status of the female adolescents and may be associated with early marriage.

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Age of onset, nutritional determinants, and seasonal variations in menarche in rural Bangladesh.

Background: Menarche is a critical transition and biological event for women. Age at menarche is an important variable for women's health and appears to be decreasing from generation to generation.Aim: This study describes the distributions of recalled age at menarche of women in three-generation families, examines generational differences, and evaluates the effects of birth mothers’ and birth grandmothers’ recalled age at menarche on their daughters.Subjects and methods: This cross-sectional investigation was performed on 214 post-adolescent girls from central Taiwan and their birth mothers and grandmothers. The descriptive analysis, analyses of mixed effect models, and multiple linear regression analyses were employed to examine the relationships of age at menarche for three generations within families.Results: The distribution of age at menarche moved significantly earlier over the three generations. The mean ages at menarche were 15.16 ± 1.75, 14.50 ± 1.50, and 13.00 ± 1.26 years for grandmothers, mot...

Eun Bl

Papers

Age and seasonal distribution of menarche in Korean girls.