Stillbirth Without Viability: An Intrapartum Diagnosis of Twin Reversed Arterial Perfusion (TRAP) Sequence in Monochorionic Twin Pregnancy.

Twin reversed arterial perfusion (TRAP) sequence is a rare complication of monochorionic twin pregnancies, characterised by a nonviable acardiac twin perfused by a structurally normal "pump" twin. We report a case of a 33-year-old woman, G4P2012, who presented at 29 weeks in advanced labour with a history of inadequate antenatal care. She delivered a live male neonate, followed by the unexpected delivery of an intrauterine mass initially suspected to be a fibroid. Further evaluation revealed the mass to be an acardiac twin, and placental examination confirmed monochorionic diamniotic placentation, establishing the diagnosis of TRAP sequence. This case highlights the critical importance of early and detailed antenatal ultrasonography in twin pregnancies. It also raises important questions regarding the classification of stillbirths in the context of severe congenital anomalies incompatible with life.