Haemorrhagic Corpus Luteum in Pregnancy

A haemorrhagic corpus luteum in pregnancy is bleeding into or from the corpus luteum, causing an enlarging painful cyst with or without rupture and haemoperitoneum. It occurs at 5 to 10 weeks, especially after ovulation induction or anticoagulation. It matters because it mimics ectopic pregnancy and can cause significant bleeding.

• Risk factors: ovulation induction, anticoagulant use, trauma, intercourse, coagulopathy.
• Most bleed only a small amount and settle.
• Rupture causes acute pain.

Women have sudden unilateral lower abdominal pain, sometimes with shoulder tip pain, and may have tenderness with guarding. Pulse and blood pressure change when bleeding is large.

• Pain starts after exertion or intercourse.
• Little or no vaginal bleeding.
• Differential diagnosis: ectopic pregnancy, ovarian torsion, appendicitis, ruptured endometrioma, miscarriage.
• Complications: haemoperitoneum, haemorrhagic shock, anaemia, torsion, pregnancy loss after surgery.

The approach is ultrasound with haemoglobin monitoring.

• Transvaginal ultrasound: complex cyst with lace like or reticular internal echoes and a retracting clot, a ring of flow and an intrauterine pregnancy; free fluid in the pelvis or Morison's pouch.
• Haemoglobin repeated every 4 to 6 hours if free fluid is present; blood group and Rhesus status; cross-match 2 units.
• Serum hCG if no intrauterine pregnancy is seen.
• Urine pregnancy test; laparoscopy if unclear.

The principle is conservative management with monitoring for stable women and surgery for instability.

• Supportive: admit; two large-bore cannulae; bed rest; IV fluid Ringer's lactate 1 litre over 1 hour if unstable; monitor pulse, blood pressure and haemoglobin; transfuse if haemoglobin is below 7 g/dL or shock.
• Pharmacological: paracetamol 1 g oral or IV 6-hourly (maximum 4 g in 24 hours); morphine 2.5 to 5 mg IV titrated for severe pain; tranexamic acid 1 g IV over 10 minutes for active bleeding; stop anticoagulants if safe; micronised progesterone 400 mg vaginally twice daily if the cyst is removed or ruptures before 10 weeks.
• Procedures: laparoscopy with evacuation of clot, haemostasis and preservation of the corpus luteum; laparotomy for severe instability.
• Special groups: Rhesus negative women give anti-D immunoglobulin 250 IU IM within 72 hours; women on enoxaparin or warfarin need specialist advice on timing.
• Red flags: systolic blood pressure below 90 mmHg, pulse above 110 per minute, falling haemoglobin, rigid abdomen.
• Follow-up: repeat scan and haemoglobin at 1 week; repeat scan at 12 to 16 weeks to confirm resolution; iron: ferrous sulphate 200 mg oral 8-hourly for 3 months if anaemic.