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Pregnancy of unknown location — MRCEM SBA MCQ

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HardObstetric and gynaecological emergenciesPregnancy of unknown locationMRCEM SBA

A 28-year-old woman attends the emergency department after a repeat scan at an early pregnancy assessment service. Eight days ago, she presented with light vaginal bleeding and a positive pregnancy test. Transvaginal ultrasonography showed no intrauterine or extrauterine gestation. Her serum hCG was 800 IU/L, rising to 1,500 IU/L 48 hours later. Today's specialist transvaginal scan again shows an empty uterus, with no adnexal mass or free fluid; serum hCG is 4,100 IU/L. The bleeding has stopped. She has no pain, is haemodynamically stable and can attend follow-up. What is the most appropriate next step?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: B — Refer immediately for senior gynaecology review.

The first scan established a pregnancy of unknown location. The 87.5% hCG rise over 48 hours made a developing intrauterine pregnancy likely and justified arranging a repeat scan, but it did not exclude an ectopic pregnancy. That repeat scan has now failed to confirm a viable intrauterine pregnancy. NICE recommends **immediate clinical review by a senior gynaecologist** at this point, even though the patient is currently well. ([nice.org.uk](https://www.nice.org.uk/guidance/NG126/chapter/diagnosis-of-viable-intrauterine-pregnancy-and-of-tubal-ectopic-pregnancy)) A further hCG measurement (A) may form part of the specialist's assessment, but arranging it instead of review misses the change in priority after the repeat scan. Another routine scan in 7 days (C) similarly prolongs follow-up when the guideline calls for immediate review. Methotrexate (D) is premature: an empty uterus and rising hCG do not, by themselves, definitively diagnose an ectopic pregnancy or establish that a viable intrauterine pregnancy has been excluded. Laparoscopy (E) may become appropriate if assessment identifies an indication for surgery, but her present findings do not establish one. She needs continued ectopic-pregnancy precautions while her pregnancy location remains unresolved. ([nice.org.uk](https://www.nice.org.uk/guidance/NG126/chapter/management-of-tubal-ectopic-pregnancy))

Reference: NICE NG126: Diagnosis of viable intrauterine pregnancy and of tubal ectopic pregnancy (17 June 2026) — https://www.nice.org.uk/guidance/NG126/chapter/diagnosis-of-viable-intrauterine-pregnancy-and-of-tubal-ectopic-pregnancy NICE NG126: Management of tubal ectopic pregnancy (17 June 2026) — https://www.nice.org.uk/guidance/NG126/chapter/management-of-tubal-ectopic-pregnancy