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Changes in age at menarche in Germany: Evidence for a continuing decline
Dörte Ostersehlt1, Heidi Danker-Hopfe1
1Department of Human Biology, University of Bremen, W-2800 Bremen 33, Germany.
Summary
Secular changes in girls
Area of Science:
- Human Growth and Development
- Reproductive Health
- Anthropometry
Background:
- Limited recent data on secular trends in female growth and maturation in West Germany.
- Previous studies indicate potential shifts in developmental milestones over time.
Purpose of the Study:
- To analyze secular changes in the age at menarche among schoolgirls in Bremerhaven, North Germany.
- To compare menarcheal ages between two cross-sectional cohorts separated by a decade.
Main Methods:
- Utilized status quo data from two cross-sectional studies conducted in 1979/80 and 1989.
- Analyzed data from 2,796 girls (1979/80) and 2,223 girls (1989), aged 10.0 to 18.5 years.
- Employed probit and logit analyses to determine age at menarche.
Main Results:
- A reduction in the average age at menarche was observed over the 10-year period.
- Probit analysis indicated a decrease from 13.30 ± 1.19 to 13.01 ± 1.21 years.
- Logit analysis, fitting the data better, showed a reduction from 13.29 ± 1.21 to 13.00 ± 1.24 years.
Conclusions:
- The study indicates a slight but statistically significant trend towards earlier menarche in North German schoolgirls between 1979/80 and 1989.
- These findings contribute to understanding secular trends in female maturation in Germany.
- Further research is needed to explore the factors influencing these observed changes.
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