Successful laparoscopic management of accessory cavitated uterine malformation misdiagnosed as non-communicating rudimentary horn in an unmarried woman

Mullerian uterine anomalies are structural defects of the female reproductive system. An accessory cavitated uterine malformation (ACUM) is a rare congenital Mullerian anomaly where an accessory cavity with normal lining of endometrium is seen within the myometrium of a normally functioning uterus. We report a case of a late-adolescence (18–21 years) girl who came with complaints of severe progressive dysmenorrhoea and chronic pelvic pain for 2 years. Ultrasound misdiagnosed it as a non-communicating rudimentary horn. On laparoscopy, a definite diagnosis of ACUM was made, followed by laparoscopic excision. The defect was sutured. Postoperatively, the patient is on regular follow-up and is asymptomatic at present.This report presents a rare case of ACUM. It is often confused with a non-communicating rudimentary horn, adenomyosis with cavity and degenerated fibroid. History and clinical examination may provide a clue but not contribute to the diagnosis; instead, MRI can provide the correct interpretation. Laparoscopic excision and suturing give symptom relief and a good fertility outcome.