A 28-year-old woman receives single-dose methotrexate 50 mg/m² for an ectopic pregnancy with β-hCG 2200 IU/L. On day 4 post-injection her β-hCG is 2350 IU/L. This finding indicates:

• A Treatment failure requiring immediate surgery
• B Methotrexate toxicity; withhold folinic acid rescue
• C Ruptured ectopic; proceed to emergency laparoscopy
• D Expected transient rise; follow-up β-hCG on day 7 is required ✓

Explanation

A transient rise in β-hCG on days 1–4 after methotrexate is expected due to continued trophoblast metabolism before drug effect. Treatment success or failure is assessed by comparing day 1 and day 7 β-hCG levels; a 15% or greater fall from day 1 to day 7 is required for success. Immediate surgery is not indicated for an asymptomatic patient with a day 4 rise alone.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.