中国九大城市女孩第二性征发育和初潮年龄调查

Secondary sexual characteristics and menses in urban Chinese girls

目的调查中国九大城市城区女孩第二性征发育以及初潮呈现的平均年龄，了解中国女孩近年青春发育的趋势，获得对青春发育评估有意义的指导性依据，探究经典的性早熟年龄界限诊断标准是否仍适用于当今的中国人群。方法全国协作性横向调查，于2003年至2005年间进行。对象为代表中国东、西、南、北、中部地区的几大城市（包括北京、天津、青岛、上海、武汉、南宁、重庆、广州、福建）城区3～19．83岁的健康女孩。采用现况法（乳房触诊、阴毛视诊）获取第二性征发育（乳房发育和阴毛发育）数据，按Tanner分期标准进行评价；发放调查表，由家长和（或）女孩本人填写初潮与否及具体日期。采用几率单位回归法（probit analysis）计算乳房发育TannerⅡ（B2）和Tannerm（B3）、阴毛发育TannerⅡ（PH2）和TannerⅢ（PH3）以及初潮（M）呈现的平均年龄及95％可信区间（凹）。结果20654个健康女孩纳入分析。中国城区女孩8岁组（中值）19．57％的女孩已呈现乳房发育。乳房发育B2和B3的中位年龄分别是9．20（95％CI：9．06～9．32）岁和10．37（95％CI：10．28—10．45）岁；阴毛发育PH2和PH3的年龄分别是11．16（95％CI：11．03～11．29）岁和12．40（95％CI：12．25—12．55）岁；平均初潮年龄为12．27（95％CI：12．16～12．39）岁。中国城区女孩的乳房发育年龄在国际较早的人群之列，近25年来初潮年龄呈提前趋势。结论中同城区女孩乳房发育年龄属世界上较早人群之列，初潮年龄呈显著年代提前趋势，因此，有必要作进一步研究，以确切界定中国城区女孩青春发育的正常参照范围，为性早熟和青春发育延迟的判定提供依据。

Objective To determine the current prevalence and mean ages of onset of pubertal characteristics in healthy urban Chinese girls. To obtain the up-to-date normal reference data for diagnosing abnormal puberty such as precocious puberty and pubertal delay. Methods A cross-sectional study of sexual maturation of healthy urban 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 in girls aged 3 to 19. 83 years, 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 （C1） for onset of breast and pubic hair development and menarche. Comparison of the mean ages for sexual development was made with other published series. Comparison of the age of menarche was also made with the five similar studies done in China in the past 25 years. Results Data were analyzed in 20 654 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）. Urban Chinese girls are experiencing breast development at young ages, among the earliest recorded worldwide. A significant downward secular trend of menarcheal age was observed since 1979. 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.