Retained Miscarriage

Retained miscarriage is persistence of products of conception in the uterus after a miscarriage, whether spontaneous, medical or surgical. It results from incomplete expulsion and matters because it causes continued bleeding, pain and infection, and can lead to adhesions.

• Can follow spontaneous, medical or surgical miscarriage.
• Risk factors: gestation above 9 weeks, low misoprostol dose, infection, uterine anomaly.
• Common cause of bleeding that persists beyond 2 weeks.

Patients have bleeding that continues or returns more than 1 to 2 weeks after the miscarriage, with cramps and sometimes offensive discharge. The uterus is bulky and the os may be open.

• Heavy or prolonged bleeding.
• Fever suggests infection.
• Differential diagnosis: incomplete miscarriage, endometritis, molar pregnancy, ectopic pregnancy, placental site subinvolution.
• Complications: haemorrhage, anaemia, pelvic infection, intrauterine adhesions, infertility.

The approach is clinical review with ultrasound.

• Transvaginal ultrasound: endometrial thickness above 15 mm, heterogeneous material with Doppler flow in the cavity.
• Urine pregnancy test positive beyond 3 weeks suggests retained tissue or ongoing pregnancy.
• Haemoglobin, blood group and Rhesus status, full blood count with white cell count.
• Histology of any tissue.

The principle is evacuation of retained tissue with antibiotics if infection is suspected.

• Supportive: IV fluids if unwell; analgesia; blood transfusion if haemoglobin is below 7 g/dL or shock.
• Pharmacological: misoprostol 600 micrograms oral as a single dose or 400 micrograms sublingual if stable and without infection; paracetamol 1 g oral 6-hourly (maximum 4 g in 24 hours); ibuprofen 400 mg oral 8-hourly with food for 3 days; amoxicillin-clavulanate 625 mg oral 8-hourly for 5 days for endometritis; ampicillin 2 g IV 6-hourly plus gentamicin 5 mg/kg IV once daily plus metronidazole 500 mg IV 8-hourly for severe infection.
• Procedures: manual vacuum aspiration under paracervical block with lignocaine 1 percent, 20 mL; evacuation under anaesthesia if bleeding is heavy; hysteroscopic resection for repeated retention or adhesions.
• Special groups: Rhesus negative women give anti-D immunoglobulin 250 IU IM within 72 hours if not already given.
• Red flags: heavy bleeding, fever above 38 degrees Celsius, offensive discharge, severe pain, shock.
• Follow-up: review at 1 to 2 weeks; ultrasound if bleeding persists; haemoglobin at 4 weeks and treatment with ferrous sulphate 200 mg oral 8-hourly for 3 months if anaemic.