Ectopic Pregnancy and Miscarriage

Classification of Miscarriage

• Threatened miscarriage: vaginal bleeding with closed cervix, viable intrauterine pregnancy on USS
• Inevitable miscarriage: heavy bleeding, open cervix, products not yet expelled
• Incomplete miscarriage: some products expelled, some retained
• Complete miscarriage: all products expelled, uterus empty on USS
• Missed miscarriage (delayed/silent): non-viable pregnancy (no fetal heartbeat or empty sac) with closed cervix and minimal bleeding
• Recurrent miscarriage: 3 or more consecutive miscarriages (affects ~1% of couples)

Diagnosis

• Transvaginal ultrasound (TVUS) is the primary diagnostic tool
• Criteria for non-viability:
  • Mean gestational sac diameter ≥25mm with no embryo (empty sac / anembryonic pregnancy)
  • Crown-rump length ≥7mm with no heartbeat
• If uncertain: rescan in minimum 7-14 days before confirming non-viability
• Never diagnose miscarriage on a single scan if there is any doubt

Management of Miscarriage

Expectant Management

• Suitable for: incomplete or missed miscarriage in clinically stable women
• Allow 7-14 days for spontaneous resolution
• Success rate: ~50% for incomplete, ~25-30% for missed miscarriage within 2 weeks
• Safety net: attend if heavy bleeding, fever, worsening pain

Medical Management

• Misoprostol: 800mcg vaginal or 600mcg sublingual
• Repeat dose if not effective within 24-48 hours
• Success rate: ~85% for incomplete, ~80% for missed miscarriage
• Suitable for gestational sac <30mm
• Side effects: cramping pain, diarrhoea, nausea, fever
• Advise on expected bleeding pattern and when to seek help

Surgical Management

• Manual vacuum aspiration (MVA) under local anaesthetic OR surgical evacuation under general anaesthetic
• Indications: patient preference, failed medical/expectant management, heavy bleeding, signs of infection, suspected molar pregnancy
• Risks: uterine perforation, cervical damage, intrauterine adhesions (Asherman syndrome), incomplete evacuation

Pregnancy of Unknown Location (PUL)

• Positive pregnancy test but no pregnancy seen on TVUS (neither intrauterine nor ectopic)
• Serial hCG monitoring:
  • hCG rising appropriately (≥63% in 48h): likely early viable IUP — rescan in 1-2 weeks
  • hCG declining: likely failing pregnancy — monitor to <5 IU/L
  • hCG rising suboptimally or plateauing: suspected ectopic — further assessment
• 50% resolve as failing PUL, 30% are early IUP, 15-20% are ectopic

Anti-D Prophylaxis

• Required: surgical management of miscarriage, ectopic pregnancy
• NOT required: threatened miscarriage <12 weeks with no intervention and bleeding has stopped
• Required from 12 weeks: all miscarriages regardless of management

Psychological Support

• Acknowledge grief — miscarriage is a significant bereavement event
• Offer follow-up appointment within 2 weeks
• Information about support organisations (e.g. Miscarriage Association)
• Consider referral for counselling if prolonged grief or mental health impact

Important Facts for MRCOG

• Non-viability criteria: CRL ≥7mm with no heartbeat, or sac ≥25mm with no embryo
• Never diagnose on a single uncertain scan — rescan in 7-14 days
• Misoprostol 800mcg vaginal is first-line medical management
• Anti-D not required for threatened miscarriage <12 weeks without intervention
• PUL: rising hCG <63% in 48h suggests ectopic
• Surgical management: MVA under local or evacuation under GA
• Recurrent miscarriage (≥3): investigate for antiphospholipid syndrome, thrombophilia, uterine anomalies, chromosomal factors

Source: NICE CG154 / NG126 (2021)

Read the original on nice.org.uk

Clinically reviewed by NHS obstetricians and gynaecologists · Source last updated 2021

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