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Age at menarche, United States.
Vital and Health Statistics. Series 11, Data From the National Health Survey
|September 12, 2014
Summary
This study estimates the average age at menarche (first menstruation) for US women using Health Examination Survey data. It also analyzes trends and differences across population subgroups over time.
Area of Science:
- Reproductive Health
- Public Health Surveillance
- Biostatistics
Background:
- The Health Examination Survey (HES) is a key program by the National Center for Health Statistics.
- HES collects physical examination, test, measurement, and questionnaire data from U.S. population samples.
- The survey comprises distinct, cross-sectional programs called 'cycles' focusing on specific population segments and health aspects.
Purpose of the Study:
- To estimate the current age at menarche for women in the United States.
- To investigate variations in age at menarche among different population subsets.
- To identify temporal changes in the age at menarche over time.
Main Methods:
- Utilized data from three completed cycles (1960-1970) of the Health Examination Survey.
- Adult female respondents in Cycle I reported their age at menarche via questionnaire.
- Parental reports provided menarche information for participants in Cycles II (ages 6-11) and III (ages 12-17).
Main Results:
- The study provides estimates for the age at menarche based on the collected HES data.
- Analysis examined demographic and temporal variations in menarcheal age.
- Specific findings on age trends and subgroup differences were derived from the data.
Conclusions:
- The Health Examination Survey data offers valuable insights into menarcheal timing in the U.S. population.
- Understanding age at menarche trends is crucial for monitoring reproductive health and population changes.
- Further analysis of HES data can reveal detailed patterns of pubertal development.
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