Secular trends in age at menarche among Chinese girls from 24 ethnic minorities, 1985 to 2010.

ABSTRACT:

Background

Declining age at menarche has been observed in many countries. In China, a decrease of 4.5 months per decade in the average age at menarche among the majority Han girls has recently been reported. However, the trends in age at menarche among ethnic minority girls over the past 25 years remain unknown.

Objectives

To compare the differences in median age at menarche among girls aged 9-18 years across 24 ethnic minorities in 2010 and to estimate the trends in age at menarche in different ethnic minorities from 1985 to 2010.

Design

We used data from six cross-sectional Chinese National Surveys on Students' Constitution and Health (1985, 1991, 1995, 2000, 2005, and 2010). The median age at menarche was estimated by using probit analysis.

Results

In 2010,

SUBMITTER: Song Y 

PROVIDER: S-EPMC4518164 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature