Objective: To evaluate resolution of serum hCG and progesterone in patients with ectopic pregnancy receiving single-dose intramuscular (IM) methotrexate as compared with those undergoing laparoscopic salpingostomy.
Methods: In this prospective randomized clinical trial, 75 hemodynamically stable women with a diagnosis of ectopic pregnancy were randomized to treatment with single-dose IM methotrexate (1 mg/kg) or laparoscopic salpingostomy. All women had initial, day 4, and weekly serum hCG and progesterone measurements taken until hCG levels were less than 15 mIU/mL. Methotrexate therapy was repeated if posttreatment day 7 hCG levels did not decrease by 15%, as compared with day 4 levels. Success rate was defined as ectopic resolution without the need for the alternate mode of therapy.
Results: Thirty-eight women were randomized to treatment with methotrexate and 37 to laparoscopic salpingostomy. The mean (+/-standard deviation) time required for serum progesterone concentrations to decrease to less than 1.5 ng/mL was significantly less for laparoscopic salpingostomy than for treatment with methotrexate: 7.8+/-1.7 and 17.6+/-2.2 days, respectively (P < .01). Within each treatment group, serum progesterone levels resolved (less than 1.5 ng/mL) more rapidly than did hCG levels (less than 15 mIU/mL) (P < .01). No further treatment was required once serum progesterone levels had decreased to less than 1.5 ng/mL. Success rates were similar in both groups: 94.7% (36 of 38) for methotrexate and 91.4% (33 of 36) for laparoscopic salpingostomy. Mean time required for hCG concentrations to decrease to less than 15 mIU/mL was significantly less for laparoscopic salpingostomy than for methotrexate therapy: 20.2+/-2.7 and 27.2+/-2.3 days, respectively (P < .05). Additional methotrexate injections were required in 15.8% (6 of 38) of women randomized to methotrexate therapy. Initial serum hCG levels for patients receiving additional methotrexate doses were 4830+/-1588 mIU/mL as compared with 2133+/-393 mIU/mL for women receiving only one dose (P = .07).
Conclusion: Serum progesterone levels of less than 1.5 ng/mL are a good predictor of ectopic pregnancy resolution regardless of treatment, and because its return to normal values occurs more rapidly than that of hCG levels, serum progesterone may be a better marker for predicting successful treatment. Although laparoscopic salpingostomy leads to faster resolution of hormonal markers of ectopic gestation, methotrexate is equally successful for treating small unruptured ectopic pregnancies. Initial hCG levels may be a marker for women requiring additional doses of methotrexate.