Cerebral palsy in preterm infants: a population-based case-control study of antenatal and intrapartal risk factors

Previous studies have indicated that foetomaternal infection increases the risk of spastic cerebral palsy (CP) in term infants, whereas this association appears to be less evident in preterm infants. The aim of this study was to analyse infection- related risk factors for spastic CP in preterm infants. A population- based series of preterm infants with spastic CP, 91 very preterm (< 32 wk) and 57 moderately preterm (32- 36 wk), born in 1983- 90, were included and matched with a control group (n = 296). In total, 154 maternal, antenatal and intrapartal variables were retrieved from obstetric records. In the entire group, histological chorioamnionitis /pyelonephritis, long interval between rupture of membranes and birth, admission- delivery interval <4 h and Apgar scores of <7 at 1 min just significantly increased the risk of CP, and Apgar scores of <7 at 5 and 10 min were strongly associated with an increased risk. Abruptio placentae, Apgar scores <7 at 1 min and pathological non- stress test (reason for delivery) were significant risk factors of CP only in the moderately preterm and hemiplegic groups, whereas fever before delivery was a significant risk factor in the very preterm and spastic diplegic groups. Antibiotics during pregnancy was associated with CP only in the spastic diplegic CP group. Conclusion: Antenatal infections marginally increased the risk of CP. Low Apgar score and abruptio placentae were associated with CP, especially in moderately preterm infants with hemiplegic CP.