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Published on: April 10, 2018
Sex differences in the prevalence of human birth defects: a population-based study
1Birth Defects and Pediatric Genetics Branch, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia 30341-3724, USA. jml2@cdc.gov
Teratology
|December 18, 2001
Summary
Male infants have a higher risk of birth defects than female infants. This study found significant sex differences in the prevalence of many congenital anomalies, particularly defects of the sex organs, urinary, and gastrointestinal tracts.
Area of Science:
- Reproductive Health
- Pediatrics
- Medical Genetics
Background:
- Sex differences in human birth defect prevalence are frequently observed but not fully characterized.
- Population-based data are crucial for understanding the extent of these sex-based disparities.
Purpose of the Study:
- To comprehensively assess sex differences in the prevalence of major birth defects.
- To quantify the male-to-female risk ratio for various congenital anomalies.
Main Methods:
- Analysis of population-based data from the Metropolitan Atlanta Congenital Defects Program (MACDP) spanning 1968-1995.
- Calculation of sex-specific prevalence and male-female relative risks for all major birth defects and categories.
Main Results:
- Overall major birth defect prevalence was higher in males (3.9%) than females (2.8%).
- Defects of sex organs, urinary tract, and gastrointestinal tract showed significantly higher prevalence in males.
- Twofold or greater sex-specific prevalence differences were common across many defect types.
Conclusions:
- Sex differences in birth defect prevalence are common, with male infants facing a greater risk.
- These findings highlight the need to investigate underlying biological and environmental mechanisms contributing to sex-based disparities in congenital anomalies.
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