A woman presents with an ectopic pregnancy at 6 weeks with β-hCG 2,200 IU/L, haemodynamically stable, no free fluid on ultrasound, adnexal mass 2.5 cm. She is treated with a single-dose intramuscular methotrexate protocol. On which day is the first follow-up β-hCG measured to assess treatment success?
- A Day 7 ✓
- B Day 1 (day after injection)
- C Day 4
- D Day 14
Correct answer: A. Day 7
Explanation
In the single-dose methotrexate protocol for ectopic pregnancy, β-hCG is measured on Day 1 (day of injection) and again on Day 4 and Day 7. Treatment is considered successful if β-hCG falls by ≥15% between Day 4 and Day 7. If the fall is inadequate, a second dose is given. Weekly monitoring continues until β-hCG is undetectable. The Day 7 measurement is therefore the key day for evaluating treatment response.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.