Ruptured Ovarian Cyst

A ruptured ovarian cyst is a break in the wall of an ovarian cyst with release of fluid or blood into the pelvis. It is most often a functional cyst, endometrioma or dermoid cyst.

• It causes sudden pelvic pain, often during exercise or intercourse, and may cause haemoperitoneum.
• Most stable women recover with observation.
• Ruptured dermoid cyst can cause chemical peritonitis.

Sudden severe lower abdominal pain, which may radiate to the shoulder, nausea, vomiting, light-headedness and abdominal tenderness.

• Rebound tenderness, tachycardia, hypotension if bleeding is heavy, free fluid in the pouch of Douglas.
• Differential diagnosis: ectopic pregnancy, ovarian torsion, appendicitis, pelvic inflammatory disease, renal colic, diverticulitis, miscarriage.
• Complications: haemoperitoneum, shock, peritonitis, adhesions and anaemia.

Diagnosis is by pregnancy test and ultrasound, with a focused scan in unstable women.

• Pregnancy test and serum beta human chorionic gonadotrophin.
• Transvaginal and abdominal ultrasound for collapsed cyst and free fluid; a focused assessment (FAST) scan in unstable women.
• Full blood count, group and cross-match, clotting screen.
• CT scan if the diagnosis remains unclear in a stable woman.
• Diagnostic laparoscopy when diagnosis is uncertain.

Observe stable women, and resuscitate and operate for ongoing bleeding or instability.

• Supportive: IV access with two large cannulae; crystalloid 500 mL IV bolus for hypotension; oxygen; monitor pulse, blood pressure and urine output; nil by mouth until stable.
• Pharmacological: paracetamol 1 g IV or oral 6-hourly (maximum 4 g in 24 hours); morphine 2.5 to 5 mg IV titrated every 5 minutes; ondansetron 4 mg IV 8-hourly for vomiting. Transfuse blood when haemoglobin is below 7 g/dL or in shock. Reverse anticoagulation (vitamin K 5 mg slow IV for warfarin with high INR).
• Procedures: observation with serial examination and haemoglobin for stable women with small free fluid; laparoscopy or laparotomy for ongoing bleeding, instability, or peritonitis, with cyst wall repair or cystectomy and washing out of blood or dermoid contents.
• Special groups: in pregnancy rule out ectopic pregnancy first, avoid ibuprofen from 28 weeks, and give anti-D immunoglobulin 250 IU IM to Rhesus-negative women after bleeding up to 20 weeks.
• Red flags: shock, falling haemoglobin, peritonitis, positive pregnancy test with pain, anticoagulant use.
• Follow-up: review at 1 week; ultrasound at 6 weeks to confirm resolution and exclude residual cyst.