The Effective Role of Adding Letrozole to Methotrexate in the Management of Tubal Ectopic Pregnancies, a Randomized Clinical Trial

Document Type : Research article


1 Yas Hospital, Tehran University of Medical Sciences, Tehran, Iran.

2 Vali-e-Asr Reproductive Health Research Center, Tehran University of Medical Sciences, Tehran, Iran.

3 Arash Women Hospital, Tehran University of Medical Sciences, Tehran, Iran.



Ectopic pregnancy (EP) is considered a main reproductive health challenge. According to the side effects of using methotrexate (MTX), it is rational to find safer drugs in the management of EP. This randomized controlled trial aimed to evaluate the efficacy and safety of adding letrozole to the single-dose MTX in the management of EPs. This study was conducted in an academic hospital affiliated to Tehran University of Medical Sciences. Women with EP and stable vital signs with β-hCG levels ≤3500 were assigned randomly to receive MTX + placebo or MTX + letrozole. The regression pattern of β-hCG, need for further surgery, and potential side effects were compared between groups. A total of 90 women were assigned equally to the study groups and were matched in age, body mass index (BMI), serum biochemistry, and primary levels of β-hCG. No drug-related side effects were observed in groups. The rates of further surgery (p = 0.614) and second dose of MTX (p = 0.809) were not significant between groups. In the MTX + placebo group, we observed a minor increase in β-hCG levels on day 4 followed by a decreasing pattern on days 7 and 14. But, in MTX + letrozole group, a decreasing pattern in β-hCG levels from day 1 through day 14 was perceived. The results support using MTX + letrozole to treat stable women diagnosed with tubal EP as a safe and efficient method. Further studies are required to evaluate letrozole alone as an alternative therapy in EPs.

Graphical Abstract

The Effective Role of Adding Letrozole to Methotrexate in the Management of Tubal Ectopic Pregnancies, a Randomized Clinical Trial


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