A 15-year-old female patient (menarche one year earlier) presented with severe dysmenorrhoea with normal menstrual flow. On the abdominal examination, fullness and tenderness was seen in the left flank. There was no history of tuberculosis or any urinary complaints. Ultrasound revealed a septate uterus with heterogeneous collection in the left uterine cavity. There was a left-sided, complex cystic lesion with haematosalpinx. Both kidneys were normally visualized. MRI was performed in a 1.5T system (Achieva, Philips Medical Systems, The Netherlands), which showed a septate uterus with normal outer fundal contour of the uterus. The left-sided cavity was obstructed with associated hematometra. There was also left haematosalpinx and endometriomas in the left ovary with loculated, hemorrhagic fluid in the lower peritoneal cavity. The right-sided uterine cavity was seen to communicate with the single cervical canal (Figures 1, 2). The patient underwent exploratory laparotomy with excision of the left-sided uterine cavity and of the left adnexal endometriotic lesions. The postoperative course was uneventful with relief of dysmenorrhoea.