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Reduced Male:Female Ratio at Birth in Small Islands
1Department of Paediatrics, Mater Dei Hospital, Malta.
The West Indian Medical Journal
|December 31, 2015
Summary
The male to female ratio at birth in equatorial island populations was lower than expected, with no observed changes over time. Further research is needed to understand the reasons for this demographic finding.
Area of Science:
- Demography
- Human Reproduction
- Epidemiology
Background:
- The expected male to female ratio at birth (M/F) approximates 0.515.
- Previous observations indicated a higher M/F in Micronesia.
- This study investigates M/F in specific island populations.
Purpose of the Study:
- To analyze the male to female ratio at birth in selected island populations.
- To identify any trends in M/F over a defined period.
Main Methods:
- Utilized World Health Organization dataset for analysis.
- Included data from Bahamas, Barbados, Puerto Rico, Trinidad and Tobago, and Mauritius.
- Analyzed live births from 1960-2009.
Main Results:
- Overall M/F was 0.5106 (95% CL 0.5101, 0.5110) across 54,086,29 live births.
- No significant secular trends in M/F were detected over the study period.
Conclusions:
- The M/F in these equatorial islands is lower than anticipated.
- The underlying reasons for this demographic observation remain unknown.
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