Tehran University Medical Journal (Jul 2014)
Predictors of single-dose methotrexate treatment failure in ectopic pregnancy
Abstract
Background: The use of Methotrexate (MTX) is a good and common practice for the treatment of women who were diagnosed early with ectopic pregnancy (EP). The aim of this study is to determine the predictors of treatment failure with a single dose of MTX injection. Methods: In this quasi-experimental research, we studied 70 women with ectopic preg-nancies who were treated with MTX, according to a single dose protocol from 2010 to 2013. EP was diagnosed whenever an intrauterine gestational sac was not identified by transvaginal ultrasonography (TVUS), accompanied by an abnormal rise or plateau in human chorionic gonadotropin (beta-hCG) concentration. Briefly, women with ectopic pregnancies were considered candidates for MTX treatment if they were hemodynami-cally stable; did not desire surgical therapy, agreed to weekly follow-up; and did not have hepatic, hematologic, or renal disease. A Patient was considered a treatment suc-cess (group 1) if her beta-hCG levels decreased ≤10 m IU/ml after the first dose of MTX. Treatment failure (group 2) was defined as the need for a second or a third dose of MTX or surgery. The following risk factors were compared between the two groups: serum beta-hCG on the days 1 and 4, a ≥ 15% decrease in serum beta-hCG between the days 1-4 of the treatment, age, parity, gravidity, the size of the ectopic mass and the endometrial thickness. Results: The success rate of MTX treatment was 77.1%. There were no significant dif-ferences between the two groups in regard to the age, parity, gravidity, the size of ec-topic mass and the endometrial thickness in vaginal sonography, but the mean serum beta-hCG concentration on days 1 and 4 was lower in the success group than the failure group. We also observed a ≥ 15% decrease in serum beta-hCG in 80.9% of the women from the success group and in 38.5% of the cases whose treatment had failed. The presence of fetal heart activity was seen in only one patient and this patient’s treatment failed. Two patients had previous history of ectopic pregnancy and the treatment of both ended in failure. Conclusion: Among women with ectopic pregnancies who were candidates for MTX treatment, a high serum beta-hCG concentration on the days 1-4 and also a ≤ 15% fall in serum beta-hCG between the days 1-4 treatment, are the most important factors associated with the failure of the treatment with a single dose MTX protocol. It is better to use these factors for making decisions about the initiation of the treatment or the continuation of it.
