Ovarian torsion: symptoms, causes and emergency treatment

The NHS lists sudden, severe and sharp pelvic pain among the symptoms that can occur if a cyst twists. NHS Borders guidance adds that ovarian torsion usually presents with abdominal or pelvic pain with nausea and vomiting, and that the pain often radiates to the loin or thigh.

Symptoms can be non-specific. On examination there may be a raised temperature, a fast heart rate, tenderness and sometimes a palpable mass, and NHS Borders notes that white cell count and CRP are only raised in about half of women with torsion, so normal blood tests do not rule it out.

History taking may reveal similar episodes in the preceding months. NHS Borders says this can represent the cyst twisting and untwisting, so a short-lived bout of severe pain that settled is still worth reporting.

• Sudden, severe, often one-sided pain low in the tummy or pelvis.

• Nausea and vomiting.

• Pain that may spread to the loin or thigh.

• Earlier brief episodes of similar pain that settled by themselves.

The ovaries sit on either side of the womb. The NHS describes an ovarian cyst as a fluid-filled sac that develops on an ovary, and says that cysts usually only cause symptoms if they split (rupture), are very large or twist and then block the blood supply to the ovary. A twist of this kind is ovarian torsion.

The NHS Borders guideline also uses the term adnexal torsion. It lists torsion alongside rupture and haemorrhage as the possibilities to consider when a woman with an ovarian cyst has acute-onset pain, and warns that torsion of other pelvic structures, for example a pedunculated fibroid, should be considered in women with known fibroids.

Torsion is most often linked to a cyst or mass on the ovary that makes it heavier or less steady. The NHS says the vast majority of ovarian cysts are non-cancerous and many cause no symptoms at all, so having a known cyst is not a reason to expect torsion, but it is a reason to know the warning signs.

NHS Borders advises that in premenopausal women a cyst larger than 7cm should be considered for surgical management because of the risk of torsion, while simple cysts smaller than 5cm typically resolve over 2 to 3 menstrual cycles without intervention. In premenopausal women it also asks clinicians to consider chronic symptoms of endometriosis, which may suggest torsion of an endometrioma, although it describes this as uncommon.

The NHS advises asking for an urgent GP appointment or getting help from NHS 111 if you have sudden, severe pelvic pain, or pain in your tummy and also feel or are being sick. NHS Borders says that women with possible torsion may present to A&E, directly to gynaecology or by referral from other specialties, and that the likelihood of preserving the ovary falls over time, so sudden severe pain should not be left to settle.

A short-lived episode of severe pain that settles may represent a cyst that twisted and untwisted. NHS Borders describes this pattern, and it is still worth reporting because it can happen again.

Sudden pelvic pain has several causes, which is one reason assessment in hospital is needed. NHS Borders lists the alternatives to consider alongside torsion.

NHS Borders guidance says that women with suspected ovarian torsion should be admitted to acute gynaecology for pain relief and investigation, have intravenous access secured and be kept nil by mouth in case surgery is needed. Investigations include a urine dip with a pregnancy test, blood tests, and an urgent ultrasound scan (transvaginal or transabdominal) with Doppler to look at blood flow. It stresses that management should not be delayed by a lack of out-of-hours scanning, and that CT or MRI may help in some cases.

It explains that a normal ultrasound does not exclude torsion and that the decision to operate may be made on clinical grounds if symptoms are severe.

The NHS Borders guideline says definitive management of ovarian torsion is surgical and should not be delayed, with the operation carried out on an emergency list at the next appropriate space. It describes surgery as usually involving removal of the ovary (oophorectomy or salpingo-oophorectomy), says that the appearance of the ovary at operation does not correlate well with whether it will recover, and says laparoscopic (keyhole) approaches reduce admission time, post-operative pain and the long-term risk of adhesions.

On the NHS cyst pages, the general principle is that surgeons aim to preserve fertility whenever possible, which may mean removing only the cyst and leaving the ovaries intact, or removing only one ovary. The NHS also says that people should talk to their surgeon about the potential effects on fertility before an operation, although in an emergency this conversation may be brief.

NHS Borders says ovarian cysts can be found in up to 5% of pregnancies but are rarely malignant, that rates of ovarian torsion are 1 to 3%, and that the risk of torsion reduces with increasing gestation, being unusual after 20 weeks.

A urine pregnancy test is part of the assessment for anyone with suspected torsion. NHS Borders says MRI may be useful in the second and third trimesters, when the ovaries and appendix are more difficult to image by ultrasound, and that surgery in pregnancy should only be performed in cases of acute abdomen or high suspicion of malignancy. If you are pregnant and have sudden severe pain, treat it as an emergency in the same way.

The NHS says ovarian cysts do not usually prevent you getting pregnant, although they can sometimes make it harder to conceive, and that surgery to remove both ovaries would mean you no longer produce eggs.

Your surgical team can explain what was found at operation and what follow-up is needed.

Ovarian torsion is an emergency, so the route into care is the emergency route. NHS Borders says women with possible torsion may present to A&E, directly to gynaecology or by referral from other specialties, and are admitted to acute gynaecology for pain relief and investigation.

Private care has a place before and after an emergency, for example scans and gynaecology consultations for a known cyst, or follow-up after surgery. It is not a substitute for emergency assessment: if you have sudden severe pelvic pain, go to A&E or call NHS 111 rather than waiting for a booked appointment.