Undiagnosed placenta accreta spectrum complicated by massive haemorrhage during mid-trimester medical termination of pregnancy: a case report

Abstract

Placenta accreta spectrum (PAS) is a well-recognised cause of severe obstetric haemorrhage in late pregnancy but is rarely encountered during abortion, particularly in the mid-trimester. Diagnosis in this setting is challenging, and unrecognised abnormal placentation may result in catastrophic maternal morbidity. We report the case of a 28-year-old multiparous woman with three prior caesareans who presented at 17 weeks of gestation with preterm prelabour rupture of membranes and placenta previa. Targeted mid-trimester ultrasound reviewed by a maternal-fetal medicine subspecialist demonstrated no sonographic features suggestive of PAS. Following counselling, medical termination of pregnancy was initiated using mifepristone and misoprostol. Uncontrolled bleeding led to timely transfer to the operating theatre for hysterotomy and management of haemorrhage. The procedure was complicated by sudden massive haemorrhage, haemodynamic collapse, and intraoperative cardiac arrest. Despite uterine evacuation and resuscitative measures, uncontrolled bleeding necessitated an emergency subtotal hysterectomy, complicated by dense vesicouterine adhesions and bladder injury. The patient survived following massive transfusion, intensive care admission, and multidisciplinary management. This case highlights the limitations of mid-trimester imaging in reliably excluding clinically significant PAS. It also underscores the potential for abrupt, life-threatening haemorrhage during medical termination of pregnancy in women with multiple previous caesarean deliveries. As caesarean rates rise, clearer guidance is needed regarding risk stratification, imaging pathways, and procedural planning for mid-trimester abortion to minimise maternal morbidity.