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Secular trends in newborn sex ratios
1Academic Department of Paediatrics, Medical School, Mater Dei Hospital, Malta.
Early Human Development
|September 16, 2014
Summary
The ratio of males to females at birth, typically favoring males, is influenced by various global factors. This includes environmental stressors like political events and man-made radiation exposure, as seen in historical incidents.
Area of Science:
- Demographics
- Environmental Health
- Human Biology
Background:
- The male-to-female ratio at birth consistently shows a male excess.
- Numerous factors are known to influence this sex ratio.
- Global variations in this ratio warrant further investigation.
Purpose of the Study:
- To provide a global overview of factors influencing the sex ratio at birth.
- To review and expand upon the author's recent research in this area.
- To highlight the impact of environmental stressors on the sex ratio.
Main Methods:
- Literature review of existing research on sex ratio determinants.
- Analysis of country-specific, regional, and continental data.
- Correlation of demographic data with environmental and political events.
Main Results:
- Stress, particularly from political events, significantly impacts the sex ratio at birth.
- Man-made radiation exposure, exemplified by the Windscale and Chernobyl disasters, demonstrably affects the sex ratio.
- Global data reveals geographical variations in the male-to-female ratio influenced by these factors.
Conclusions:
- Environmental factors, including stress and radiation, are critical determinants of the sex ratio at birth.
- Understanding these influences is crucial for public health and demographic studies.
- Further research is needed to fully elucidate the complex interplay of factors affecting the sex ratio.
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