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Updated: Aug 4, 2026
10:57
Determining Soil-transmitted Helminth Infection Status and Physical Fitness of School-aged Children
Published on: August 22, 2012
Summary
This study tracked puberty in Zambian school children. Pubic and axillary hair appeared around age 9-10, with the earliest menarche at 9.4 years and a mean of 13.7 years.
Area of Science:
- Pediatrics
- Human Growth and Development
- Public Health
Background:
- Puberty onset varies globally.
- Understanding Zambian children's pubertal development is crucial for health monitoring.
Purpose of the Study:
- To document the timing of pubertal milestones in Zambian school children.
- To establish normative data for pubertal development in this population.
Main Methods:
- Cross-sectional study of 2,638 Zambian school children (1,220 boys, 1,418 girls) in Lusaka.
- Assessed physical indicators: pubic hair, axillary hair, breast development (Tanner stages), and menarche.
- Data collected through observation and self-reporting.
Main Results:
- Pubic and axillary hair first appeared in 9-year-old girls and 10-year-old boys.
- Breast bud development (Stage 2) was observed starting at age 9 in girls.
- The earliest menarche occurred at 9.4 years, with a mean age of 13.7 years for Zambian school girls.
Conclusions:
- The study provides key data on the timing of puberty in Zambian children.
- Findings can inform pediatric health assessments and interventions in the region.
- Establishes a baseline for future longitudinal studies on pubertal development in Zambia.
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