Spontaneous retroperitoneal haematoma in pregnancy secondary to ruptured ovarian artery aneurysm: a case report

Rupture of an ovarian artery aneurysm is a rare but potentially life-threatening cause of retroperitoneal haemorrhage during pregnancy. Most reported cases have occurred postpartum in multiparous women. This report describes an unusual case in a 26-year-old primigravid woman with symptom onset in the second trimester. She presented with recurrent left-sided abdominal pain from 21 + 6 weeks of gestation. Following repeated normal initial assessments, CT angiography at 31 + 6 weeks revealed a ruptured left ovarian artery aneurysm with retroperitoneal haemorrhage. She underwent a successful transarterial embolization, later developed pre-eclampsia, and delivered a healthy infant by planned caesarean section at 37 + 3 weeks of gestation. The case demonstrates that pregnancy-associated ovarian artery aneurysm may rupture in nulliparous women and present as early as the second trimester with recurrent, non-specific abdominal pain. Early vascular imaging and timely intervention may improve maternal and fetal outcomes.