EP16.30: Subamniotic hematoma causes fetal anemia

A 34-year-old at 27+5 weeks presented with early-onset FGR. Her ultrasound screening at 28+6 weeks demonstrated a single viable fetus with an EFW of 625 grams (<3rd percentile). There were multiple hypoechoic placental cysts (~ 6 cysts) arising from placental surface. Such cysts were of clear content and occupied >50% of the placental area (see figure 1). The largest cyst was about 5.8 x 4.2 x 3.1 cm in size. The amniotic fluid appeared to be echogenic but normal amount. The patient was admitted and antenatal corticosteroid was administered to promote lung maturity and expectant management with continuous maternal and fetal surveillance was performed. Six days after the admission (29+4 weeks of gestation), there were non-repetitive variable decelerations with worsening of fetal Dopplers; occasional reversed a-wave of DV. Therefore, a Caesarean delivery was performed. Intraoperative findings demonstrated turbid yellowish amniotic fluid without blood clots in the amniotic cavity and multiple placental cysts; varying in size with various colours of cysts content. The neonate was diagnosed with mild anemia (Hct 39.9%).The neonate also had respiratory distress and she was admitted in the neonatal intensive care unit for 32 days. Newborn septic work ups demonstrated no bacterial growth on hemoculture. Gross placental pathology showed multiple stages of sub-amniotic cysts. Microscopic placental examination demonstrated nucleated RBC in amniotic membrane, positive CD71 (fetal RBC staining), hemosiderin-laden macrophages engulfed iron in the chorioamniotic membranes (see figure 1). Fluids from placental cysts cell block showed presence of fresh and old red blood cells. Blood from placental cysts was proven to be of fetal origin from Kleihauer Betke and Hb typing tests (see figure 1). Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.