Chorioamnionitis and Cerebral Palsy in Term and Near-Term Infants
- Yvonne W. Wu, MD, MPH;
- Gabriel J. Escobar, MD;
- Judith K. Grether, PhD;
- Lisa A. Croen, PhD;
- John D. Greene, MA;
- Thomas B. Newman, MD, MPH
- Author Affiliations: Departments of Neurology (Dr Wu), Pediatrics (Drs Wu and Newman), and Epidemiology and Biostatistics (Dr Newman), University of California, San Francisco; Kaiser Permanente Division of Research, Oakland, Calif (Drs Escobar and Croen and Mr Greene); and California Department of Health Services, Sacramento (Dr Grether).
Abstract
Context Half of all cases of cerebral palsy (CP) occur in term infants, for whom risk factors have not been clearly defined. Recent studies suggest a possible role of chorioamnionitis.
Objective To determine whether clinical chorioamnionitis increases the risk of CP in term and near-term infants.
Design, Setting, and Patients Case-control study nested within a cohort of 231 582 singleton infants born at 36 or more weeks' gestation between January 1, 1991, and December 31, 1998, in the Kaiser Permanente Medical Care Program, a managed care organization providing care for more than 3 million residents of northern California. Case patients were identified from electronic records and confirmed by chart review by a child neurologist, and comprised all children with moderate to severe spastic or dyskinetic CP not due to postnatal brain injury or developmental abnormalities (n = 109). Controls (n = 218) were randomly selected from the study population.
Main Outcome Measure Association between clinical chorioamnionitis and increased risk of CP in term and near-term infants.
Results Most CP cases had hemiparesis (40%) or quadriparesis (38%); 87% had been diagnosed by a neurologist and 83% had undergone neuroimaging. Chorioamnionitis, considered present if a treating physician made a diagnosis of chorioamnionitis or endometritis clinically, was noted in 14% of cases and 4% of controls (odds ratio [OR], 3.8; 95% confidence interval [CI], 1.5-10.1; P = .001). Independent risk factors identified in multiple logistic regression included chorioamnionitis (OR, 4.1; 95% CI, 1.6-10.1), intrauterine growth restriction (OR, 4.0; 95% CI, 1.3-12.0), maternal black ethnicity (OR, 3.6; 95% CI, 1.4-9.3), maternal age older than 25 years (OR, 2.6; 95% CI, 1.3-5.2), and nulliparity (OR, 1.8; 95% CI, 1.0-3.0). The population-attributable fraction of chorioamnionitis for CP is 11%.
Conclusion Our data suggest that chorioamnionitis is an independent risk factor for CP among term and near-term infants.
- KEYWORDS:
- cerebral palsy
- chorioamnionitis
- infant
