Fetal DNA levels in maternal blood correlated with fetal prognosis in a case of intervillous hematoma.

Several methods for detection of fetal components in maternal blood have been reported. However, few have proven clinically useful for determining the treatment in cases of placental injuries. Here, we report a case of extensive intervillous hematoma diagnosed at 25 weeks of gestation with severe intrauterine growth restriction and oligohydramnios. Marked elevation of fetal DNA levels was observed in maternal blood. Fetal DNA levels decreased after 27 weeks of gestation, concurrent with recovery of fetal growth. We conservatively managed this case until 30 weeks of gestation, when a male infant was delivered. He weighed 508 g and displayed Apgar scores of 7 at 1 minute and 9 at 5 minutes. Histological examination of the placenta revealed intervillous thrombosis without infarction or inflammatory changes. In this case, decreasing fetal DNA levels in maternal plasma correlated with recovery of fetal growth and provided useful information for fetal management as well as insight into the pathogenesis of placental injuries.