Maternal, neonatal, and placental features associated with diffuse chorioamniotic hemosiderosis, with special reference to neonatal morbidity and mortality

Objective. Our purpose was to examine the significance of diffuse chorioamniotic hemosiderosis (DCH) on neonatal morbidity and mortality. Methods. Using data from a retrospective case-control study, we analyzed 46 singleton placentas with DCH from infants who were delivered and/or admitted to the neonatal intensive care unit of Kanagawa Children's Medical Center during 1987 - 2001 and 92 control placentas without DCH from infants of comparable gestational age, birth weight, and duration. Results. Mean and standard deviation of gestational age and infants' birth weight at delivery from the DCH group were 27 +/- 3 weeks and 939 +/- 342 g, respectively. Macroscopically, the placentas with DCH were more likely to show old peripheral blood clots (46% in the DCH group vs 8% in control group), subchorionic hematoma (20% vs 1%), and circumvallation (13% vs 1%). Histologically, amniotic necrosis was significantly more frequent in the DCH group (63% vs 24%). Of the obstetric factors, incidence of recurrent episodes of vaginal bleeding (70% vs 11%), oligohydramnios (59% vs 8%), and chronic abruption-oligohydramnios sequence (57% vs 5%) were significantly higher in the DCH group. Of the neonatal factors, persistent pulmonary hypertension of the newborn (29% vs 8%) and dry lung and/or pulmonary hypoplasia ( 20% vs 4%) were more common. However, respiratory distress syndrome was rare (15% vs 45%) in the DCH group. Neonatal death including stillbirth was increased in the DCH group but was not significant ( 24% vs 15%). Of infants who survived beyond day 28, chronic lung disease (CLD) was more frequent in the DCH group (51% vs 22%). The association of DCH, especially accompanied by amniotic necrosis, with CLD was still evident using likelihood ratio test. Conclusion. DCH is closely associated with preterm delivery, pulmonary hypertension of the newborn, and dry lung syndrome and is a significant risk factor for CLD.