Chronic peripheral separation of placenta. The significance of diffuse chorioamnionic hemosiderosis.

Diffuse nonmeconium-related pigment was observed in the chorioamnion of 36 of 1,023 placentas over 4 years and evaluated by iron staining. Stains were negative in 13 cases and positive in chorionic plate and membranes (diffuse chorioamnionic hemosiderosis [DCH]) in 23 cases (3/1,000 deliveries; 25/1,000 placentas). Gestational age at delivery was lower in DCH and was inversely proportional to the magnitude of iron staining. Placentas with DCH were more likely to show circumvallation, old peripheral blood clots, increased chorionic-villous macrophages, and green discoloration. To evaluate demographic, obstetric, and perinatal factors associated with DCH, 2 gestational age-matched controls were selected for each DCH case. Multiparity, smoking, and chronic vaginal bleeding all were increased significantly with DCH, while intrauterine growth retardation and oligohydramnios were increased but did not achieve statistical significance. Gestational hypertension and advanced maternal age were significantly decreased with DCH, and cocaine abuse was uncommon (3 cases). Long-term neurologic sequelae of DCH were evaluated in a separate series of gestational age-matched very-low-birth-weight infants with and without neurologic impairment at 2 years of age. No increased risk of neurologic impairment was found in patients with DCH.