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Updated: Aug 4, 2026

Determining Soil-transmitted Helminth Infection Status and Physical Fitness of School-aged Children
Published on: August 22, 2012
Abstract:
A cross sectional study of 2,638 Zambian school children 1,220 boys and 1,418 girls has been done in Lusaka to study the puberty process. Public and axillary hair, breast development and menarche were studied. Pubic hair appeared for the first time in the group of 9 year-old girls and 10 year-old boys. Axillary hair appeared at about the same time. Stage two of the breast bud appeared for the first time in the group of 9 year-old girls. The earliest case of occurrence of menarche was in a girl of 9.4 years. The mean age at menarche in Zambian school girls was 13.7.
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