Objective: To determine whether congenital anomalies are associated with breech presentation at the time of birth.
Study design: A population-based, retrospective cohort study was conducted among 460,147 women with singleton live births using the Missouri Birth Defects Registry, which includes all defects diagnosed during the first year of life. Maternal and obstetric characteristics and outcomes between breech and cephalic presentation groups were compared using χ(2)-square statistic and Student's t-test. Multivariable binary logistic regression analysis was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).
Result: At least one congenital anomaly was more likely present among infants breech at birth (11.7%) than in those with cephalic presentation (5.1%), whether full-term (9.4 vs 4.6%) or preterm (20.1 vs 11.6%). The relationship between breech presentation and congenital anomaly was stronger among full-term births (aOR 2.09, CI 1.96, 2.23, term vs 1.40, CI 1.26, 1.55, preterm), but not in all categories of anomalies.
Conclusion: Breech presentation at delivery is a marker for the presence of congenital anomaly. Infants delivered breech deserve special scrutiny for the presence of malformation.