Cerebral palsy in term infants: a clinicopathologic analysis of 158 medicolegal case reviews.

Our understanding of cerebral palsy (CP) in term infants is hindered by its low incidence and sporadic presentation. Many of these CP cases enter litigation, and a focused review of medicolegal consultations provides an opportunity to better understand the pathogenesis of these cases. In this study complete clinical and pathologic data from 158 cases of CP complicating singleton pregnancies after 36 weeks of gestation were prospectively collected over a 10-year period extending from 1998 to 2008. A hierarchical system was used to separate cases into the following 5 groups: (1) clinical/sentinel events (20%), (2) severe large fetoplacental vascular lesions (34%), (3) placental lesions indicative of chronic placental dysfunction (23%), and (4) placental lesions indicative of subacute/chronic adaptation to hypoxia (15%). The remaining 8% (group 5) of cases were idiopathic. Common to all subgroups was clinical and/or pathologic evidence of umbilical cord obstruction, which was observed in 63% of cases. The following clinical features significantly differed among subgroups. Group 1 had less maternal obesity and more cases involving multicystic encephalopathy. Group 2 had increased oligohydramnios, cerebral edema, nucleated red blood cell counts greater than 10 000/mm(3), hypoglycemia, pulmonary hypertension, and cardiac dysfunction. Group 3 had more preeclampsia and, together with group 2, more infants with a low ponderal index. Group 5 had a higher prevalence of positive family history of neurodevelopmental disorders. In conclusion, infant cases subject to litigation related to CP following term birth can be separated into distinct clinicopathologic subgroups with only a small number lacking either clinical/sentinel events or placental evidence of subacute or chronic in utero stress.