Ovarian torsion
Sudden one-sided pelvic pain with vomiting. A normal Doppler doesn't exclude torsion; laparoscopy does.
A 24-year-old woman has had sudden, severe right lower abdominal pain for 4 hours with vomiting. She had a similar, shorter episode last week that settled. Pregnancy test negative. Temperature 37.4 °C. Tender right iliac fossa with a vague adnexal mass. Ultrasound: a 7 cm right ovarian cyst, with Doppler flow present.
Does present Doppler flow rule out torsion, and what happens next?
- Sudden severe one-sided pelvic pain with vomitingThink torsion.
- Pregnancy testAlways: ectopic is the key differential.
- Analgesia, antiemetic, IV accessBloods: FBC, CRP, group and save.
- Pelvic ultrasound with DopplerEnlarged ovary, mass, whirlpool sign, oedema. Normal flow does not exclude torsion.
- Clinical suspicionGynae registrar for laparoscopy. Don't wait for "absent flow".
- At surgeryUntwist and preserve the ovary, even if it looks dark.
- PregnantTorsion is more common in early pregnancy, same urgency.
- Sudden severe pelvic pain with vomiting
- Ovarian mass with pain
- Positive pregnancy test with pain (ectopic first)
- Peritonism or shock
- Pain in a girl or adolescent
- Ectopic pregnancy
- Appendicitis
- Ruptured or haemorrhagic cyst
- Pelvic inflammatory disease
- Kidney stone
- Tubo-ovarian abscess
| Typical mass | Ovarian cyst or tumour 5 cm or more (often benign dermoid) |
| Doppler flow present | Does not exclude torsion |
| Treatment | Laparoscopic detorsion, preserve the ovary |
| Pregnancy | Higher risk in the first trimester and with ovarian stimulation |
| Children | Torsion can happen with a normal ovary |
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On this page
Who gets it?
- Ovarian mass 5 cm or more (cysts, dermoids, benign tumours).
- Reproductive age most often; also children and adolescents (sometimes with a normal ovary).
- Pregnancy (especially first trimester) and ovarian stimulation for fertility treatment.
- Previous torsion.
Clinical features
- Sudden, severe, one-sided lower abdominal or pelvic pain, sometimes radiating to the back, flank or thigh.
- Nausea and vomiting (common).
- Previous similar episodes that settled (intermittent twisting).
- Low-grade fever if the ovary is dying.
- Tender adnexa, sometimes a mass. Peritonism if necrosis.
Diagnosis
Ectopic until proven otherwise
Torsion likely: gynae, laparoscopy
PID or tubo-ovarian abscess
Appendicitis
Doppler flow can be present in torsion because the ovary has a double blood supply and the twist may be partial. Diagnosis is clinical. Laparoscopy confirms and treats.
Investigations
| Test | Why |
|---|---|
| Urine or serum hCG | Exclude pregnancy and ectopic |
| FBC, CRP | Infection, bleeding |
| Group and save | Theatre |
| Urine dipstick | Stones, infection |
| Transvaginal or transabdominal ultrasound with Doppler | Mass, enlarged oedematous ovary, whirlpool sign |
| CT | If the diagnosis is unclear and pregnancy excluded |
| Tumour markers (CA-125 and others) | If a mass looks suspicious (don't delay surgery) |
Management
- Resuscitate and relieve painIV access, analgesia, antiemetic, nil by mouth.
- Pregnancy test and ultrasoundQuickly.
- Gynae registrarLaparoscopy as soon as possible.
- DetorsionUntwist and preserve the ovary even if it looks dark and swollen. Function often recovers.
- CystRemoved at the same time or later.
Oophorectomy only if the ovary is clearly dead and falling apart, or if malignancy is suspected in a postmenopausal woman.
Treatment
See ectopic pregnancy and appendicitis.
Common mistakes
- Ruling out torsion because Doppler shows flow.
- Skipping the pregnancy test.
- Sending home a woman whose pain "settled" after a similar episode.
- Removing a dark ovary that could recover.
- Forgetting torsion in children and in pregnancy.
Frequently asked questions
Does normal Doppler flow exclude ovarian torsion?
No. Flow can be present in torsion. The diagnosis is clinical and confirmed at laparoscopy.
What is the treatment for ovarian torsion?
Urgent laparoscopy to untwist the ovary and preserve it where possible.
Who is at risk of ovarian torsion?
Women with ovarian masses of 5 cm or more, pregnant women, women having fertility treatment, and children.
Should a dark ovary be removed after detorsion?
Usually not. Function often recovers, so the ovary is preserved unless clearly dead or malignancy is suspected.
Test yourself
Exam-style questions on this guide, from our two question banks. Choose an answer to see why each option is right or wrong.
1. A 23-year-old with a 6 cm ovarian cyst has sudden severe one-sided pelvic pain and vomiting. Doppler shows flow in the ovary. What is the next step?
Answer: Gynaecology review for laparoscopy. A normal Doppler does not exclude torsion. If the history fits, laparoscopy is diagnostic and therapeutic.
- Discharge, as flow excludes torsion: Flow can persist in torsion.
- Oral contraceptive pill: Not for acute pain.
- CT in a month: Delay.
- Repeat ultrasound in 6 weeks: Delay.
2. At laparoscopy, a twisted ovary looks dark blue-black. What is the usual action?
Answer: Untwist and preserve it. Detorsion with conservation is recommended even if the ovary looks dark; most regain function.
- Hysterectomy: No.
- Leave it twisted: No.
- Remove both ovaries: No.
- Remove the ovary: Most recover after detorsion.
3. Which is the first test for a woman of reproductive age with acute pelvic pain?
Answer: Pregnancy test. Ectopic pregnancy must be excluded first.
- Laparoscopy: Not before a pregnancy test.
- CA-125: Not first.
- Pelvic MRI: Not first.
- Blood culture: Not first.
4. A 22-year-old woman has sudden severe right iliac fossa pain with vomiting after exercise. Pregnancy test is negative. Ultrasound shows a 7 cm right ovarian cyst with reduced blood flow and a "whirlpool" sign. What is the management?
Answer: Laparoscopic detorsion. Ovarian torsion presents with sudden unilateral pelvic pain, nausea and vomiting, usually with an ovarian mass. Doppler flow may be normal, so clinical suspicion is key. Urgent laparoscopy to detort the ovary preserves it in most cases, even if it looks dark — removal is only for clear necrosis.
- Analgesia, review in 6 weeks: Delay leads to ovarian infarction.
- Oral antibiotics for PID: Antibiotics treat PID; this is ovarian torsion (whirlpool sign, reduced flow), a surgical emergency.
- Combined pill to shrink the cyst: The pill does not shrink an existing cyst quickly and cannot untwist a torted ovary; delay means losing the ovary.
5. A 25-year-old has a 6 cm ovarian cyst. Ultrasound shows echogenic fat, hair and calcification (a tooth). What is the commonest complication?
Answer: Torsion. Mature cystic teratoma (dermoid cyst) is the commonest ovarian germ cell tumour and the commonest ovarian neoplasm in young women; contains skin, hair, sebaceous material, teeth, bone (ectodermal dominance). Bilateral in ~10%. Complications: torsion (commonest — heavy, mobile), rupture (chemical peritonitis), rarely malignant change (squamous carcinoma in older women), struma ovarii (thyroid tissue → hyperthyroidism). Treat by laparoscopic ovarian cystectomy.
- Malignant transformation: Malignant change is rare (under 2%).
- Rupture with peritonitis: Rupture is uncommon.
- Pseudomyxoma peritonei: Pseudomyxoma is linked with mucinous tumours.
6. In each menstrual cycle many follicles start developing but usually only one ovulates. What happens to the rest?
Answer: Atresia. About 7 million oocytes exist at 20 weeks of fetal life, 1–2 million at birth and about 400,000 at puberty; only about 400 ovulate. Each cycle a cohort is recruited; the dominant follicle (most FSH receptors, most aromatase) survives as FSH falls, while the others undergo atresia by apoptosis.
- They ovulate later: Only the dominant follicle ovulates.
- They become corpora lutea: Only the ovulated follicle forms a corpus luteum.
- They wait for the next cycle: Recruited follicles do not wait.
- They form ovarian cysts: Not normal fate.
7. At 6 weeks of pregnancy, a woman needs laparoscopic removal of a twisted ovary that contains the corpus luteum. Which of the following is the most appropriate step afterwards?
Answer: Progesterone support until about 10 weeks. In early pregnancy, hCG from the syncytiotrophoblast keeps the corpus luteum alive, and its progesterone maintains the decidua. The placenta gradually takes over progesterone production between about 7 and 10 weeks (the luteoplacental shift). If the corpus luteum is removed before this, progesterone falls and the pregnancy may miscarry, so progesterone is given until about 10 weeks. After that, removal of the corpus luteum does not threaten the pregnancy.
- No treatment; the placenta takes over now: The placenta is not yet producing enough progesterone at 6 weeks.
- Oestrogen support until delivery: Oestrogen does not maintain the decidua in this way.
- hCG injections until 20 weeks: hCG cannot act once the corpus luteum is removed.
- Bed rest alone for two weeks: Rest does not replace the lost progesterone.
References and dose sources
- ACOG Committee Opinion 783: Adnexal torsion in adolescents
- RCOG — Green-top guidelines
- NICE NG126 — ectopic pregnancy and miscarriage
- Morphine dosing: Drugs.com: Morphine dosage (see also our morphine dose page)
- Ondansetron dosing: Drugs.com: Ondansetron dosage (see also our ondansetron dose page)
- Paracetamol dosing: Drugs.com: Acetaminophen (paracetamol) dosage (see also our paracetamol dose page)
International guidance is linked where it reflects good practice. Where your hospital’s protocol differs, follow your hospital.