Treating Persistent Ectopic Pregnancy by Methotrexate Using a Sliding Scale: Preliminary Experience

ABSTRACT

To assess the clinical utility of prescribing a sliding scale regimen for methotrexate administered in cases of persistent ectopic pregnancy, a prospectively designed clinical trial was performed. Patients (n = 37) previously operated on for ectopic pregnancy by laparoscopic salpingostomy and found to have persistent disease were enrolled into the study. Methotrexate was given intramuscularly at a dose of 1 mg/kg body weight, with the number of doses administered depending on the presenting level of serum beta-human chorionic gonadotropin (β-hCG). Group 1 (n = 27), levels of 10–1500 mIU/ml, received a single dose; group 2 (n = 5), levels of 1500–2500 mIU/ml, received two doses 3 days apart; group 3 (n = 5), levels >2500 mIU/ml, received three doses 3 days apart. Patients were followed with weekly transvaginal ultrasound examinations, and serum β-hCG and progesterone measurements. Results noted resolution in all three treatment groups without the requirement of surgery or further treatment: group 1, 19.9 ± 1.7 days; group 2, 35.2 ± 4.5 days; group 3, 49.0 ± 1.0 days. All patients remained asymptomatic, and no adverse side effects from the drug were experienced. We conclude, although preliminary, that a sliding scale approach to prescribing methotrexate based on the initial serum titer of β-hCG to treat persistent ectopic pregnancy is easy to use, efficacious, and likely results in complete resolution of the condition. In most cases, even with presenting levels of β-hCG > 2500 mIU/ml, persistent disease will resolve within 50 days of initiating care. (J GYNECOL SURG 13:13, 1997)