Ovarian torsion

Ovarian torsion occurs when an ovary twists on the tissue that supports it, cutting off its blood supply. It is an uncommon but serious complication that can occur after ovarian stimulation, when the ovaries are enlarged and heavier than usual, making them more prone to twisting. It causes sudden, severe, one-sided pelvic or lower abdominal pain, often with nausea and vomiting. Suspected ovarian torsion is a medical emergency, because delay in treatment can risk permanent loss of the ovary. Anyone with sudden severe pelvic pain during or after fertility treatment should contact their fertility clinic immediately and, if it cannot be reached quickly or symptoms are severe, go straight to the nearest hospital emergency department. Diagnosis is usually made with ultrasound, and surgery is often needed to untwist or, in some cases, remove the affected ovary. Women with larger or multiple ovarian cysts, or a strong response to stimulation medicines, may be at somewhat higher risk, and this can be discussed with the treating clinic as part of overall risk counselling before and during stimulation.

Also known as: twisted ovary, ovary torsion

Last reviewed: 9 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.