Letrezole or clomide for ovulation induction in patients with unexplained infertility.


  • Nadia Saddam AL Assady Lecturer in obstetrics and gynecology department. College of medicine / Thiqar university.



The aim of our study to compare the efficacy of letrezole to clomiphene citrate in patient with unexplained infertility as empirical treatment.


200 patients with unexplained infertility randomly divided into two groups the first group received( 5mg letrezole from the day 3-7 of menstrual cycle), the second group received (100 mg clomiphene citrate from the day 2-5 of menstrual cycle), follicular development followed by serial U/S, when one or more follicles reach > 18mm in diameter ovulation trigger by hCG and timed intercourse was advise later on . Pregnancy test was performed 5 days after the miss period to confirm the pregnancy, the main outcome was the pregnancy rate and the secondary outcome was follicle development and endometrial thickness.


Both groups were comparable regarding the ovulation rate (62.5% in the group B ( clomid group ) and 75.2% in group A ( letrezole group ) ( P = 0.35 ), the endometrial thickness was statistically significant difference in the letrzole group on day of HCG administration ( 6.6_+1.69 mm in the letrezole group, 5.4_+1.61 mm in the clomide group, P < 0.001). Serum estradiol was significantly lower in letrezole group ( 456_+150 versus 922_+301 pg/ml, P < 0.001). While the rate of multiple follicular development was greater in the group B ( clomide  55.15%, letrezole 25.41%, P=0.025), which was statistically significant. The pregnancy occurred in 36 out 100 (36% ) in letrezole group and 12 out 100 ( 12% ) in clomide group, the difference was highly statistically significant ( P < 0.025 ).


Letrezole had a good efficacy and may be regard as first line treatment in patients with unexplained infertility in comparison with clomiphene citrate


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