Outcome of methotrexate treatment for ectopic pregnancies among obese women

Single dose administration of methotrexate (MTX) is considered the first line of treatment in selected patients with an ectopic pregnancy (EP). However, data regarding MTX efficacy among obese patients is limited. We sought to investigate the efficacy of MTX single dose regimen among obese patients MATERIAL AND METHODS: A retrospective cohort study conducted at a gynecology department in a tertiary teaching hospital, between January 2010 and December 2018, including women diagnosed with an EP and treated by a single-dose regimen of MTX. We compared success rate and gestation characteristics between obese and non-obese women.

Overall, 195 women were treated with single-dose intramuscular MTX for EP during the study period. Of those, 31 women (15.9%) were obese (BMI ≥ 30 kg/m²) and the rest 164 (84.1%) were of normal body weight. Median MTX dosage for the obese group was 95 milligrams (IQR 91-104) vs. 83 milligrams (IQR 78-87) for the non-obese group. Treatment success rate of the overall cohort was 66.6% (130/195) and treatment success rate of single-dose MTX was comparable between the obese and non-obese groups (64.5% vs. 67.0%, p = 0.78). Obese patients were older as compared to non-obese (median age 33 vs. 29, p = 0.03). In multivariate logistic regression analysis, percentage hCG change from day 1 to day 4 was the only factor associated with treatment success (aOR 1.02; 95%CI 1.01, 1.04, p < 0.001).

Single-dose MTX treatment among obese patients diagnosed with ectopic pregnancy led to similar success rates as compared to non-obese patients.