Some Structural Congenital Anomalies Are More Common in Males

Most studies of the prevalence of structural malformations in male and female newborns have focused on specific anomalies or all anomalies combined. In this analysis, using data on 2,537,001 live- and stillborn offspring of women in California, the investigators focused on differences in risk between male and female offspring.

Overall, 33,107 males and 22,315 females were found to have structural congenital anomalies. After excluding birth defects seen only in males, such as genital or sex chromosome anomalies, the investigators found that birth defects occurred in 2.25% of males and 1.75% of females -- a 28.6% higher prevalence in males than in females. Certain birth defects, such as central nervous system abnormalities, dislocated hips, an…