OBJECTIVETo investigate major risk factors for childhood cerebral palsy (CP) during pregnancy and to provide evidence for the prevention of CP.

METHODSUsing the search terms of "cerebral palsy", "pregnancy", "risk factor", and "case-control", a search was performed to collect case-control studies on the risk factors for childhood CP from 1998 to 2011. The obtained data were subjected to metaanalysis using fixed effects model and DersimonionLaird random effects model to quantitatively evaluate risk factors for childhood CP during pregnancy.

RESULTSEighteen studies involving 11050 cases and 15941 controls were collected. The results of the multivariate analysis for risk factors of childhood CP during pregnancy were as follows: maternal age (≥35 years) (OR = 4.172, 95%CI = 1.670-10.426, P < 0.05), multiple pregnancy (OR = 8.402, 95% CI = 2.386-29.584, P < 0.05), medicine use in early pregnancy (OR = 3.974, 95% CI = 2.217-7.123, P < 0.05), harmful environment (OR = 3.299, 95% CI = 1.058-10.289, P < 0.05), recurrent vaginal bleeding during pregnancy (OR = 4.736, 95% CI = 1.792-12.517, P < 0.05), pregnancy infectious diseases (OR = 1.238, 95%CI: 0.284-5.395, P > 0.05), pregnancy induced hypertension (OR = 4.096, 95%CI: 2.246-7.469, P < 0.05), meat intake (OR = 1.436, 95%CI:0.382-5.393, P > 0.05), father smoking (OR = 2.376, 95%CI: 0.801-7.049, P > 0.05).

CONCLUSIONSThe major risk factors for childhood CP during pregnancy include advanced maternal age (≥35 years), multiple pregnancy, medicine use in early pregnancy, harmful environment, recurrent vaginal bleeding during pregnancy and pregnancy-induced hypertension.