Letrozole Versus Gonadotropins for Ovulation Induction in Clomiphene Citrate Resistance: A Randomized Controlled Study

This study included 70 patients enrolled according inclusion and exclusion criteria. The inclusion criteria were (a) Infertility lasting one year or more in presence of regular intercourse, (b) Patients' age between 20-35years (c) Normal semen analysis according to WHO 2010 (d) Patent fallopian tubes (e) Normal prolactin and TSH. (e) Anovulatory cycles confirmed by mid-luteal progesterone ≤ 3 ng/ml and (f) Clomiphene citrate resistance for 3 cycles of 150mg. Exclusion Criteria were (a) Any hormonal disturbances eg. hyperprolactinemia, (b) Immunological causes of infertility, (c) Coital errors, (d) Metabolic disorders and (e) Poor patient compliance.

Sample size calculation: The minimum sample size calculated using Epi info program version 7 for unmatched case control study; 80% power and 95% Confidence interval was 22 for each group. For better accuracy and validity of results the sample size was increased by 10%=3 in each group. The total number of cases was 50 and 25 for each group.

Randomization and allocation: It was a prospective quesi-randomization. Based on the attendance order, patients with odd numbers were considered group I (Letrozole group) and those with even numbers were considered group II (Gonadotropin group). Allocation was equal 1:1.

Intervention:

Group I (Letrozole Group n=25): These patients were treated with letrozole (Femara®, Novartis New York, NY, USA) in a dose 2.5 mg (one tablet daily) orally began on the 3rd day to the 7th day of the cycle. If ovulation is not achieved dose is increased by 2.5 mg in next cycle till 3 cycles. If hyperstimulation occurred, the cycle was cancelled and the patients were excluded from the study.