The present investigation on the secular trend in the sexual maturation—breast and pubic hair development, and age of onset of menarche—of southern Chinese girls in Hong Kong was carried out in 1961-63 and 1977-79 on two different groups of girls, 9-20 years of age. It was shown that in the 1977-79 girls there are no differences between the sexual maturation of the girls of the upper and the lower socioeconomic strata because the socioeconomic conditions have improved considerably, and the improvement is relatively more marked in the lower socioeconomic stratum. It was also demonstrated that there is a significant secular acceleration in the sexual maturation of the girls and this is obviously a trend towards earlier maturation. When the secular trend of the girls of the upper and the lower socioeconomic strata are considered separately, there is only a significant downward trend in the ages of sexual maturation of the girls of the lower socioeconomic stratum and not of the upper socioeconomic stratum. It is suggested that the environmental and particularly nutritional differences and the differences in the availability of pediatric care that distinguished the socioeconomic classes and possibly influence the sexual maturation of the girls have more or less disappeared.
Low, W D.; Kung, L S.; and Leong, J C.Y
"Secular Trend in the Sexual Maturation of Chinese Girls,"
3, Article 11.
Available at: https://digitalcommons.wayne.edu/humbiol/vol54/iss3/11