Skip to textbook content
Doctor’s PassportTextbook
QuestionsFlashcardsBriefsDashboardAccount
TopicsAll topics

Loading topic navigation…

Textbook navigation
TopicsAll topics

Loading topic navigation…
Educational draft · awaiting clinical reviewUse Rapid for revision, not patient-care decisions. Check current national and local guidance and the BNF or BNFC before acting.

Pregnancy of unknown location

Obstetrics and gynaecology · UK scope · Sources checked 27 Aug 2026 · Clinical review pending

RapidFull
!
Symptoms outrank the hCG curve

New severe unilateral pain, shoulder-tip pain, syncope, haemodynamic change, peritonism or increasing bleeding in a pregnancy of unknown location may indicate rupturing ectopic pregnancy at any hCG value.

Action: Use ABCDE, obtain urgent senior gynaecology review, venous access, bloods and crossmatch as needed, and move to emergency ultrasound or surgery without waiting for the next planned hCG.

Synopsis

Manage a positive pregnancy test with no pregnancy seen on ultrasound as a temporary high-risk state until location and outcome are established safely.

  • Pregnancy of unknown location is an ultrasound classification: the pregnancy test is positive but transvaginal ultrasound shows neither definite intrauterine nor definite extrauterine pregnancy.
  • Possible outcomes are an early viable intrauterine pregnancy, a failing intrauterine pregnancy that has not been documented, or an ectopic pregnancy; the label is not a final diagnosis.
  • Assume ectopic pregnancy remains possible until location is established or follow-up demonstrates complete resolution.
  • Take two serum hCG measurements as close as possible to 48 hours apart, but no earlier; use them to plan follow-up, never to assign anatomical location.
  • A rise greater than 63% suggests a developing intrauterine pregnancy but does not exclude ectopic; arrange transvaginal ultrasound in 7–14 days, earlier when hCG is at least 1,500 IU/L.
  • A fall greater than 50% suggests a pregnancy unlikely to continue; arrange a urine test 14 days after the second blood test and review within 24 hours if it remains positive.
  • A rise below 63% or fall below 50% requires clinical review in the early-pregnancy service within 24 hours because ectopic or persisting PUL is more likely.
  • Do not use serum progesterone, a single discriminatory hCG threshold or reassuring absence of risk factors to close the pathway.

Key red flags

Haemodynamic instability, collapse, pallor, tachycardia, hypotension or peritonism requires direct emergency care and resuscitation rather than outpatient serial testing.

Shoulder-tip pain, severe unilateral pelvic pain, rectal pressure or pain on movement may reflect intraperitoneal blood even when vaginal bleeding is light.

A rising hCG does not exclude ectopic pregnancy, and a falling hCG does not prevent rupture; any symptom change triggers reassessment regardless of the prior trend.

Loss to follow-up while location remains unknown is a safety failure; confirm contact details, ability to return and a functioning 24-hour escalation route before discharge.

Investigation priorities

01
Transvaginal ultrasoundFirst step

Search for a definite intrauterine pregnancy, adnexal ectopic features and haemoperitoneum with the most sensitive early approach.

Management branches

Immediate dangerTreat possible rupture first

A patient with PUL develops haemodynamic change, severe pain, peritonism, syncope or significant bleeding.

  1. Activate ABCDE care, two large-bore cannulas, urgent bloods and group-and-save or crossmatch, analgesia and senior gynaecology and anaesthetic support.
  2. Use bedside or urgent formal imaging only if it does not delay definitive control; free fluid plus shock is enough to prioritise emergency surgery.
  3. Continue resuscitation, blood-product support and operative preparation while communicating uncertainty and obtaining consent to the extent the emergency permits.
Stable first assessmentCreate the 48-hour plan

The patient is clinically stable and ultrasound meets the definition of PUL.

  1. Review symptoms, observations, examination, risk factors and scan quality and obtain the first quantitative hCG without using it to name the location.
  2. Book the second hCG as near as possible to 48 hours later, confirm reliable contact and give written emergency symptoms and a 24-hour service number.
  3. Document pregnancy intention, communication needs and exact responsibility for checking results so a missed sample or non-attendance triggers active follow-up.
Open full textbook →Answer 2 questions
Sources and review status4 sources · checked 27 Aug 2026 · clinical review pending+
Sources

Sources and review status

National guidance is shown before implementation-dependent detail. Apply principles in context and verify current guidance when a decision affects care. Source check completed 27 Aug 2026; clinical approval remains outstanding.

  • NICE NG126 pregnancy location diagnosisPUL definition, hCG thresholds, ultrasound and follow-up.
  • NICE NG126 ectopic symptomsAtypical symptoms, emergency referral and initial assessment.
  • RCOG ectopic pregnancy informationPatient-centred diagnosis, treatment and future-pregnancy advice.
  • NHS ectopic pregnancySymptoms and urgent help-seeking.

Editorial contact: Doctor’s Passport editorial team. Source-check date is separate from clinical approval. Report a content problem · Content changes

Authoring stateRapid draftClinical stateAwaiting reviewJurisdictionUnited Kingdom