The purpose of this study is to determine the presence and severity of abnormalities in placental pathology which may occur in premature newborns who develop periventricular leukomalacia (PVL) postnatally. To accomplish this, the medical records of all preterm newborns (<34 weeks) born between 1990-1995 with head ultrasound evidence of PVL, and whom had placental pathology performed were reviewed (N=31). These patients were matched for gestational age and birthweight to preterm newborns born during the same period without PVL, whom also had placental pathology performed (N=65). Head ultrasounds were done one time per week during the first 6-8 weeks of life. Placentas were examined by one pathologist for the presence of chorioamnionitis, funisitis, and infarction or calcification. Placental weight(prior to being trimmed) was also recorded, and results are presented for singleton pregnancies only. Because of the possible effect of chorioamnionitis upon placental weight, placental weight data was further analyzed for singleton pregnancies without evidence of chorioamnionitis. Mean birthweight was 1.1±0.33 (SD) kg for patients developing PVL, and was 1.1±0.39 kg for patients without PVL (p=NS). Mean gestational age was 28±2 weeks for patients with PVL, and was 28±3 weeks for patients without PVL (p=NS). Apgar scores did not differ between groups. The frequency of chorioamnionitis did not differ between groups (15 of 31 [48%] with PVL v 33 of 65 [50%] without PVL, p=NS). The frequency of funisitis and placental calcification or infraction also did not differ. For singleton pregnancies, placental weight for PVL patients (N=23) was 270±79 grams, and was 305±99 grams for patients without PVL(N=43, p<.05) For singleton pregnancies without evidence of chorioamnionitis, placental weight for PVL patients (N=10) was 222±69 grams, and was 304±121 grams for patients without PVL (N=21, p<.001). These results indicate that PVL developing in the preterm neonate postnatally is associated with lower placental weight, particularly in the absence of chorioamnionitis. Chorioamnionitis per se is not associated with PVL.