Pooling of blood between the chorion, a membrane surrounding the embryo, and the uterine wall

Aetiology

• Can be caused by separation of the chorion from the endometrium

Clinical features

• Bleeding
• Cramping
• Threatened miscarriage
• Symptoms and course follow size and perpetuation
• Large haematomas may be source of infection, irritability (causing cramping) and miscarriage

Investigations

• Ultrasound

Management

• Usually self-limiting and resolve
• Reassurance important but surveillance should remain