Abstract
Background
Although letrozole has been used for ovulation disorders in intra-uterine insemination (IUI) for a long time, the dose and method used have not been determined.
Methods
This randomized clinical trial was conducted in 200 eligible infertile women who were candidates for IUI. They were randomly divided into two groups: in the first group, a single dose of 20 mg of letrozole tablet prescribed on the third day of the cycle, and in the second group, on the third to the seventh days of the cycle, 5 mg of letrozole tablets were prescribed every day (in total, 25 mg in divided doses). The patients underwent transvaginal ultrasound on days 9–11 of the cycle, and the size of the follicles and the thickness of the endometrium were examined and if the patient's follicles were suitable, IUI was performed.
Findings
137 patients (69%) had one or more follicles higher than 14 mm. The mean (SD) diameter of the largest follicle and endometrial thickness were 15.0 ± 2.9 mm and 5.5 ± 1.4 mm, respectively, which were not significantly different between the two groups (P > 0.05). Pregnancy occurred in 62 patients (31%) and in 10 patients (5%) abortion occurred in the first trimester with no significant difference between the two groups (P > 0.05).
Conclusion
Prescribing letrozole 20 mg as a single dose on the third day of the cycle to stimulate ovulation in IUI cycles has comparable effects with 5 divided doses of 5 mg on the third to seventh days of the cycle.
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In this study, all provisions of the Declaration of Helsinki were observed. Participation in the study was optional, and written consent was obtained from all patients upon entering the study. This study has a code of ethics from the ethics committee of Shahid Beheshti University of Medical Sciences with the code IR.SBMU.MSP.REC.1401.375 and is registered on the Iranian clinical trials website with the code IRCT20220412054511N1.
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Dr. Elham Hashemi: Obstetrics and Gynecology Specialist; Dr. Zahra Heidar: Associate Professor of Obstetrics and Gynecology.
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Hashemi, E., Heidar, Z. Comparison of Administration of Letrozole 20 mg Single Dose Versus 25 mg in Divided Doses to Stimulate Ovulation in IUI Cycles. J Obstet Gynecol India (2024). https://doi.org/10.1007/s13224-024-01956-y
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DOI: https://doi.org/10.1007/s13224-024-01956-y