Clinical overview
Ectopic pregnancy is the diagnosis that earns the most maternal mortality reviews and the most legal cases against gynaecologists, because the path to a poor outcome is almost always delayed recognition. The pathophysiology is at Ectopic pathophysiology; here we cover what to do at the bedside, the operational algorithm, the three modalities of treatment (expectant, medical, surgical), and the management of difficult sites (interstitial, cervical, scar, ovarian, abdominal, heterotopic).
The single-line summary every registrar should internalise: Any woman of reproductive age with abdominal pain, a positive pregnancy test, and no intrauterine pregnancy on transvaginal ultrasound has an ectopic until proven otherwise. This holds for IUD users, ART patients, postpartum women, sterilised women — anyone. Resist the urge to make a benign diagnosis early.
Core knowledge
Clinical presentations
The "classic triad" — amenorrhoea, pain, bleeding — is present in only ~50%. More commonly:
- A young woman in early pregnancy with one-sided pelvic pain and minimal bleeding.
- A woman on her "period" (which is actually decidual cast) with worsening unilateral pain.
- Shoulder-tip pain, syncope on standing, vague malaise — haemoperitoneum.
- IUD user with new pelvic pain — exclude ectopic.
- ART patient with abdominal pain regardless of intrauterine sac visualised — heterotopic.
Initial triage
- Unstable: shocked, tachycardic, peritonitic → resuscitate + theatre, do not delay for imaging.
- Stable but symptomatic: full workup with TVS + serum β-hCG → decide management.
- Asymptomatic with positive pregnancy test and uncertain location: pregnancy of unknown location (PUL) protocol.
Resuscitation in suspected rupture
- Two large-bore IV access.
- Crystalloid 1–2 L; permissive hypotension to systolic 80–90 mmHg until haemostasis.
- Group-specific or O-negative blood while cross-match runs.
- Activate massive transfusion protocol if hypotension persists.
- Inform theatre, consultant, anaesthetist, blood bank simultaneously.
- FBC, U&E, coagulation, lactate, group-and-cross-match (4 units), fibrinogen.
Definitive diagnosis
TVS diagnosis: an empty uterus, tubal ectopic, separate ovary, and free pelvic fluid.
Transvaginal ultrasound — the cornerstone:
- Look for an intrauterine pregnancy first.
- If not seen, scan adnexa systematically for: gestational sac with yolk sac or embryo at extrauterine site; "ring of fire" on Doppler (peritrophoblastic flow); haematosalpinx (tubal mass with mixed echogenicity); free fluid (anechoic = simple; echogenic = blood).
- Scan the CS niche specifically for scar ectopic.
- Note ovarian position relative to any adnexal mass.
Serum β-hCG quantitative. Use the dynamics:
- ≥3500 IU/L with no IUP on TVS → ectopic until proven otherwise.
- 1500–3500 IU/L with no IUP → high suspicion; close monitoring.
- <1500 with no IUP → PUL; repeat in 48 h.