Optimized Letrozole Dose Versus Traditional Use of Clomiphene Citrate for Ovulation Induction in Patients With PCOS: A Prospective Randomized Controlled Trial
DOI:
https://doi.org/10.17140/GOROJ-3-128Keywords:
Polycystic ovary syndrome, Letrozole, Clomiphene citrate, Ovulation inductionAbstract
Objective: To compare the effects of gradually increased letrozole dose in versus Clomiphene Citrate (CC) (100 mg) for ovulation induction in women with polycystic ovary syndrome (PCOS).
Design: Prospective randomized controlled trial.
Setting: IVF unit at Minia Maternity University Hospital in Egypt.
Patient(s): Two hundred infertile women with PCOS defined according to Revised Rotterdam criteria.
Intervention(s): patients were randomly allocated into two groups; study group (100 patients) receiving gradually increased doses of letrozole starting with 2.5 mg on cycle day 3 with incremental increase of 2.5 mg daily till reaching a dose of 10 mg daily on cycle day 6 and a control group (100 patients) receiving CC at a dose of 100 mg daily for 5 days starting from cycle day 3. Patients were followed up for three treatment cycles. The primary outcome was clinical pregnancy rate and the secondary outcome was number of mature follicles, endometrial thickness, serum progesterone and time to reach a dominant follicle.
Result(s): The two groups were similar in the demographic features and baseline hormonal milieu. There was no significant difference between the two groups as regards the number of mature follicles and the time to reach mature follicles. Endometrial thickness on HCG day was significantly higher in the letrozole group as compared with CC group (10.1±0.22 mm vs 8.2±0.69 mm, p=0.01)). Serum progesterone was higher in letrozole group than in CC group (19.3±3.1 vs 15.3±2.2, p<0.01). Ovulation was achieved in165/242 cycles (68.2 %) in the letrozole group and 169/249 cycles (67.9 %) in the CC group which was not statistically significant. Clinical pregnancy rate was significantly higher in letrozole group in comparison with CC group (14.8 % vs 10.4 %, p<0.01).
Conclusion(s): Letrozole in gradually increased dose achieves higher clinical pregnancy rate as compared with the traditional dose of CC. Therefore, it can be used as a first-line treatment for ovulation induction in women with PCOS.
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