Rudimentary horn pregnancy with a live fetus: emergency management of a 24-year-old patient presenting with acute abdomen — a case report and review of surgical strategy

Abstract

• Background: Rudimentary horn pregnancy (RHP) is a rare Müllerian anomaly with high risk of rupture and catastrophic hemorrhage. Early recognition and definitive surgical management improve maternal outcomes.
• Case presentation: A 24-year-old woman presented with acute right lower quadrant pain and perineal pressure. Ultrasound suggested a live intra-abdominal/adnexal fetus at ~14 weeks with a normal uterus and ovaries; β-hCG markedly elevated; Hb 10 g/dL. Laparotomy revealed a rudimentary horn pregnancy with a fetus, attached right fallopian tube, and 30 mL clotted blood in the right adnexa. The rudimentary horn and ipsilateral tube were excised; transfusion given (1 unit whole blood, 4 units FFP). Postoperative course: stable, uncomplicated.
• Conclusion: Suspect rudimentary horn pregnancy in reproductive-age women with adnexal mass and elevated β-hCG; prompt surgical excision of the rudimentary horn and ipsilateral tube is recommended to prevent rupture and preserve the remaining uterine tissue.
• Keywords: rudimentary horn, Müllerian anomaly, ectopic pregnancy, obstetric surgery, emergency laparotomy