Missed Miscarriage

Missed miscarriage is intrauterine death of the embryo or fetus before 24 weeks with retention in the uterus, a closed cervical os and often no bleeding. It is usually due to chromosomal abnormality. It matters because it is found at routine scanning, retained products can lead to coagulopathy after prolonged retention, and management choices differ.

• Common cause of early pregnancy loss.
• Risk factors: maternal age, smoking, thyroid disease, diabetes, uterine anomalies.
• May be silent until a scan or pregnancy symptoms fade.

Patients may report loss of pregnancy symptoms such as nausea and breast tenderness, or brown discharge, with no or little pain. The uterus is smaller than dates and the os is closed.

• Bleeding may be light or absent.
• No fetal movement or heart sounds on Doppler after 10 to 12 weeks.
• Differential diagnosis: threatened miscarriage, anembryonic pregnancy, ectopic pregnancy, molar pregnancy, wrong gestational dates.
• Complications: haemorrhage, infection, disseminated intravascular coagulation after more than 4 weeks of retention, psychological distress, Asherman syndrome after curettage.

The diagnosis is made on transvaginal ultrasound.

• Crown rump length 7 mm or more with no cardiac activity, or mean sac diameter 25 mm or more with no embryo, confirms the diagnosis.
• Repeat the scan after 7 to 10 days if findings are borderline.
• Haemoglobin, blood group and Rhesus status; platelets and clotting tests if retention is prolonged or bleeding is heavy.
• Urine pregnancy test remains positive and is not diagnostic.

The principle is to offer expectant, medical or surgical evacuation after confirming the diagnosis and ruling out infection.

• Supportive: counselling about options and grief; analgesia; safety netting for bleeding.
• Pharmacological: misoprostol 800 micrograms vaginally, repeat once after 3 hours if no bleeding; if no expulsion within 24 hours repeat the full course once; where mifepristone is available, give mifepristone 200 mg oral then misoprostol 800 micrograms vaginally 24 to 48 hours later; paracetamol 1 g oral 6-hourly (maximum 4 g in 24 hours); ibuprofen 400 mg oral 8-hourly with food for 3 days; metoclopramide 10 mg oral 8-hourly for nausea.
• Procedures: manual vacuum aspiration up to 12 weeks size with paracervical block (lignocaine 1 percent, 20 mL); surgical evacuation under anaesthesia for larger uteri or heavy bleeding or infection.
• Special groups: Rhesus negative women give anti-D immunoglobulin 250 IU IM within 72 hours of evacuation.
• Red flags: heavy bleeding, fever above 38 degrees Celsius, offensive discharge, collapse, bleeding from other sites.
• Follow-up: urine pregnancy test at 3 weeks; review histology; offer contraception; investigate after 3 consecutive losses.