Utilizing Repetitive Serial Placental Ultrasounds for Diagnosing a Massive Subchorionic Thrombohematoma: Insights Into Soluble FMS-Like Tyrosine Kinase-1/Placental Growth Factor (sFlt-1/PlGF) Trends.

The patient, a 34-year-old primigravida with no prior medical history, presented at 23 + 0 weeks with gestational hypertension and fetal growth restriction (FGR). Ultrasound examination showed a placental mass, and subsequent repeated ultrasound scans revealed changes in the mass' echogenicity, raising suspicion of a massive subchorionic thrombohematoma (MST). While the blood pressure was mildly elevated without proteinuria and organ dysfunctions, serum soluble fms-like tyrosine kinase-1/placental growth factor (sFlt-1/PlGF) ratios showed significantly elevated values. A cesarean section was performed at 29 + 2 weeks due to the nonreassuring fetal status. The female infant, with Apgar scores of 1/1 at one/five minutes and an umbilical artery pH of 7.16, remained unresponsive and died seven hours postdelivery. Pathology examination revealed a massive hematoma in the subchorionic space, measuring 22 mm thick, directly beneath the umbilical cord attachment. This case underscores the importance of repetitive placental ultrasound in MST diagnosis and suggests the potential utility of sFlt-1/PlGF ratios in predicting adverse outcomes.