Obstetrics & Gynaecology/Antiprogestogen + prostaglandin

Mifepristone + misoprostol

also: medical TOP · medical management of miscarriage · antiprogestogen

Overview

The medical regimen for termination of pregnancy, medical management of miscarriage, and induction for intrauterine fetal death.

Mechanism

Mifepristone is a competitive antiprogestogen (and antiglucocorticoid): blocking progesterone causes decidual breakdown, sensitises the myometrium to prostaglandins, and softens/dilates the cervix. Misoprostol (PGE₁ analogue) given 24–48 h later drives uterine contractions and expulsion.

Indications

Medical termination of pregnancy
Medical management of miscarriage
Induction of labour for intrauterine fetal death

The agents

Mifepristoneantiprogestogen

oral, then wait 24–48 h

Priming step.

MisoprostolPGE₁ analogue

vaginal/buccal/SL

Expulsion step; also used alone in some protocols.

Adverse effects

Cramping pain + bleeding (expected)common

Nausea, vomiting, diarrhoeacommon

Misoprostol.

Incomplete miscarriage / retained productsserious

Haemorrhage, infectionserious

Cautions & contraindications

Ectopic pregnancyall

Medical management is for intrauterine pregnancy.

Chronic adrenal failure (mifepristone — antiglucocorticoid)all

Severe uncontrolled asthma (mifepristone)all

Interactions

NSAIDs do not reduce misoprostol efficacy (safe for analgesia)

Monitoring & kinetics

Confirm complete expulsion (pregnancy test / scan); anti-D if RhD-negative

Mifepristone oral → misoprostol after an interval.

Source: NICE NG140 — Abortion care · BNF — Mifepristone / misoprostol