Placental Abnormality Causing Preterm Premature Rupture of Membrane

A circumvallate placenta is a form of extrachorial placenta with a raised placental margin in an annular shape. Circumvallate placenta often causes persistent vaginal bleeding beginning in the first trimester, preterm premature rupture of membranes (PPROM), preterm delivery, and placental abruption, thus being associated with poor pregnancy outcomes. A case of circumvallate placenta is reported here, which led to preterm premature rupture of membranes (PPROM) and leakage in a mother at 17 weeks of gestation. She was the second gravida with a 10-year-old healthy daughter. The mother underwent amniocentesis after the triple marker test showed an increased risk for trisomy 21. Difficulty in aspirating amniotic fluid was encountered due to the abnormal placental structure, which was not known at the time of the invasive procedure. The mother experienced leaking 7 days post-procedure, followed by miscarriage. Autopsy examination revealed that the placenta was circumvallate, which not only caused difficulty in aspirating the amniotic fluid but also could be the cause of PPROM, a well-known complication of the circumvallate placenta. This is the first case where difficulty in aspirating amniotic fluid was encountered. The circumvallate placenta group shows poor pregnancy and delivery outcomes. The circumvallate placenta may lead to vaginal bleeding during the second trimester, PPROM, and preterm delivery. This study highlights that examining the placenta is very important to identify the cause of events in certain situations; circumvallate placenta or abnormal placenta can be suspected in cases where hindrance is encountered (not able to aspirate amniotic fluid even if the needle is visible in the amniotic sac) during amniocentesis.