Ultrasound differential diagnosis between amniotic fluid sludge and blood clot from placental edge separation

Abstract

A 32-year-old G3P1011 patient was followed for a history of loop electrosurgical excision procedure and short cervix in a previous pregnancy. Early transvaginal cervical length at 16 weeks was within normal limits. During a transvaginal ultrasound at 18 weeks of gestation, cervical length was noted to be 3.5 cm. Behind the cervix, amorphous particulate matter was visualized in the amniotic fluid. The matter appeared heterogeneous, wispy, and adjacent to the internal cervical os, but also abutting the edge of the posterior low-lying placenta (Figure, A, yellow arrow; Video).