Is cerebral palsy associated with birth defects other than cerebral defects?
The objective of the study was to identify the origin (s) of the association between cerebral palsy (CP) and birth defects in the absence of cerebral birth defects. Data from the 1980 to 1994 Western Australian birth cohorts (355 659 neonatal survivors) were linked to the Cerebral Palsy Register (941 links) and the Birth Defects Registry (17070 links). Associations between CP (congenital or acquired) and birth defects (cerebral or exclusively non-cerebral) were estimated. The origin of the association between non-cerebral defects and acquired CP was investigated with an observational study, and the origin of the association between non-cerebral defects and congenital CP was investigated with a blinded case-control study of births with non-cerebral defects with or without CP. With non-cerebral defects, the odds ratio for CP was 4.8 (95% CI 3.1-7.4) if acquired and 4.7 (3.9-5.7) if congenital. For acquired CP, the association arose primarily as a result of cardiac defects. For congenital
