Ovarian Cyst Torsion and Vanishing Twin Syndrome in an Ovulation-induced First-trimester Pregnancy: A Rare Case Report.

A case of 25-year-old primigravida with 8 weeks of pregnancy presented to gynaecology outpatient department with severe abdominal pain. The patient has been receiving treatment outside and conceived after ovulation induction and timed intercourse. She was diagnosed with twisted ovarian cyst, twin pregnancy, and sepsis. Laparotomy was performed and a right sided salpingo-oophorectomy was carried out immediately. Histopathological examination revealed a haemorrhagic cyst. Throughout the antenatal period she was monitored closely. Initially she had a twin pregnancy at the time of laparotomy and also at 12th week scan. However, by the 5th month congenital anomaly scan only a singleton pregnancy was detected. Ultimately, she delivered at term via caesarean section for pregnancy induced hypertension and polyhydramnios. The baby is doing well. Patient who conceived after ovulation induction can present with twisted ovarian cyst due to enlarge ovary caused by the effects of the treatment. It is essential to consider twisted ovarian cyst as a differential diagnosis in pregnant patients presenting with acute abdominal pain during first trimester.