Pregnancy complicated by diffuse chorioamniotic hemosiderosis: obstetric features and influence on respiratory diseases of the infant.

Aim: To clarify the clinical features of pregnancy and neonatal respiratory problems associated with diffuse chorioamniotic hemosiderosis (DCH).

Methods: Sixteen singleton cases of DCH without chorioamnionitis (CAM) were retrospectively analyzed and compared with gestation- and birthweight-matched controls (32 cases of CAM and 32 cases of non-DCH-non-CAM). Maternal symptoms and respiratory problems of the infants were investigated.

Results: All 16 cases with DCH resulted in preterm delivery from 23 to 35 weeks' gestation. The presence of subchorionic hematoma in the first trimester (P < 0.001), recurrent vaginal bleeding (P < 0.001), brownish amniotic fluid (P < 0.001) and amniotic necrosis or degeneration (P < 0.001) were significantly more frequent in the DCH group compared to the CAM and non-DCH-non-CAM groups. The incidence of dry lung syndrome and persistent pulmonary hypertension of the newborn (PPHN) was significantly higher in the DCH group than in the CAM (P < 0.001) and non-DCH-non-CAM (P < 0.001) groups.

Conclusion: Long-term exposure to degenerating red blood cells is supposed to damage amnion, fetal alveolar epithelial cells and fetal pulmonary arteries, and may lead to dry lung syndrome and PPHN in the infant complicated by DCH.