Developmental effects on neonatal mortality and subsequent cerebral palsy in infants exposed to intrauterine infection

Abstract

Background Intrauterine bacterial infection is important as a high risk factor associated with subsequent brain damage of the newborn. Aims To see if mature fetuses require both hypoxia and intrauterine infection to lead to cerebral palsy, while premature fetuses need infection alone. Study design A retrospective cohort study. Subjects 230 singleton live-born infants of 22 to 32 weeks of gestation, exposed to intrauterine infection during labor and delivery, from 1995 to 2002. Methods Mortality and incidence of cerebral palsy at 2 years old were compared among the 3 groups; immature ( n = 89, 22-27 weeks), premature ( n = 73, 28-33 weeks) and mature ( n = 68, > 34 weeks). The relationship between cerebral palsy and fetal pH values was examined. Outcome measures Mortality and cerebral palsy. Results Mortality and cerebral palsy were significantly decreased with advancing gestation. Mortality was significantly decreased after 28 weeks of gestation while cerebral palsy was significantly decreased after 34 weeks of gestation. Acidosis was associated with cerebral palsy in mature infants, but not in less mature infants. Conclusions: Premature infants were more susceptible to intrauterine infection to cause death or cerebral palsy than mature infants. Mature infants may require exposures to both infection and hypoxia but less mature infants need infection alone to cause cerebral palsy, suggesting different pathogenesis during the developmental stage.