Inevitable and Incomplete Abortion
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Direct answer
Inevitable abortion is bleeding with an open cervical os and products that will be expelled, while incomplete abortion is an open os with retained products after partial expulsion. Both need prompt assessment for haemorrhage and sepsis, with haemodynamic stabilisation first and evacuation of the uterus as definitive treatment. Manual vacuum aspiration or suction curettage is the usual method, and misoprostol may be used in selected cases.
What you must remember
- Inevitable abortion: open os with bleeding and membrane rupture or products in the cervical canal; miscarriage cannot be prevented.
- Incomplete abortion: open os with retained products after partial expulsion, often with heavy bleeding.
- Missed abortion: a dead fetus retained with a closed os, diagnosed by absent cardiac activity.
- Haemodynamic stabilisation: two large-bore intravenous lines, crystalloid, and blood transfusion for significant anaemia or haemorrhage.
- Septic abortion: fever, uterine tenderness and foul discharge, treated with broad-spectrum antibiotics and urgent evacuation.
- Adjuncts: misoprostol in selected cases (WHO: 600 micrograms oral or 400 micrograms sublingual for incomplete abortion; other guidelines use 800 micrograms vaginally); ergometrine is avoided in hypertension.
A pathway from resuscitation to follow-up
Incomplete and inevitable abortion are managed in a fixed order: stabilise, diagnose, then evacuate. The steps below follow that sequence.
- Stabilise first: check pulse, blood pressure and haemoglobin, insert two large-bore lines and start crystalloid; transfuse for haemorrhage.
- Confirm the diagnosis: examine the os with a speculum to see products, and use ultrasound to confirm retained tissue where needed.
- Screen for sepsis: measure temperature, check uterine tenderness and discharge, and start antibiotics with cultures if infection is suspected.
- Plan evacuation: perform manual vacuum aspiration or suction curettage, with sharp curettage as an alternative when equipment is limited.
- Use adjuncts selectively: misoprostol in selected cases; avoid ergometrine where hypertension is present.
- Confirm and follow up: check that the uterus is empty, offer contraception counselling, and assess Rh status for anti-D.
Evacuation is the definitive step, and the stabilisation that precedes it is what keeps the woman safe during the procedure.
Where the exam tries to catch you
Questions in this area test the open-os distinction, the sepsis warning and the drug contraindications.
- Trap: Using ergometrine routinely for bleeding from incomplete abortion. Correct: Ergometrine is contraindicated in hypertension and must be used only when that is excluded.
- Trap: Waiting for spontaneous expulsion in incomplete abortion with heavy bleeding. Correct: Heavy bleeding needs prompt evacuation after stabilisation.
- Trap: Treating septic abortion as a simple incomplete abortion. Correct: Fever and foul discharge need antibiotics and urgent evacuation.
Frequently asked questions
How does inevitable abortion differ from threatened abortion?
In inevitable abortion the cervical os is open and miscarriage cannot be prevented, while threatened abortion has a closed os. Inevitable abortion usually involves more bleeding and membrane rupture. Management moves from supportive care to evacuation.
What is the definitive treatment for incomplete abortion?
Evacuation of retained products of conception is the definitive treatment for incomplete abortion, after haemodynamic stabilisation. Manual vacuum aspiration or suction curettage is commonly used. Management also includes checking for sepsis and anaemia.
When is misoprostol used in incomplete abortion?
Misoprostol is used in selected cases of incomplete abortion as an alternative or adjunct to evacuation. Regimens vary: WHO suggests 600 micrograms orally or 400 micrograms sublingually, while some guidelines use 800 micrograms vaginally. Its use depends on gestation, facilities and local protocol.
What is the first step in managing septic abortion?
Stabilise the woman, start broad-spectrum intravenous antibiotics, and arrange urgent evacuation of the uterus. Septic abortion is recognised by fever, uterine tenderness and foul discharge. Cultures are sent where possible before antibiotics are given.