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Seasonal variations in menarche in Oslo
Annals of Human Biology
|January 1, 1982
Summary
This study on adolescent girls in Oslo reveals a consistent bimodal seasonal pattern in menarche incidence between 1965-1970, with peaks in winter and summer. This finding offers insights into environmental influences on reproductive maturation.
Area of Science:
- Pediatrics
- Reproductive Health
- Epidemiology
Background:
- Understanding seasonal variations in menarche is crucial for reproductive health research.
- Previous studies have reported diverse seasonal patterns in menarche incidence across different populations.
Purpose of the Study:
- To investigate seasonal variations in menarche incidence among adolescent girls in Oslo, Norway.
- To analyze the temporal trends and seasonal patterns of menarche over a defined period.
Main Methods:
- Utilized data from approximately 11,000 girls aged 10-18 years in Oslo.
- Employed a statistical method accounting for age-structure changes over time to analyze incidence patterns.
Main Results:
- Identified a stable bimodal seasonal pattern in menarche incidence from 1965-1970.
- Observed peaks in menarche incidence during December-January and July-August.
- Noted that this pattern aligns with findings from Sweden and Finland but differs from Copenhagen data.
Conclusions:
- The study confirms a distinct bimodal seasonal variation in menarche in Oslo.
- The observed pattern suggests potential environmental influences on the timing of puberty.
- Further research is needed to elucidate the specific environmental factors driving these cyclic variations.
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