Letrozole and metformin versus letrozole alone for ovulation induction in women with polycystic ovarian syndrome: a randomised controlled trial

Polycystic ovary syndrome is a syndrome with a complex interaction between metabolic, endocrine, genetic, and environmental factors. The aim of the study is to compare letrozole and metformin with letrozole alone for ovulation induction. This was a single blinded randomized controlled trial. Patients who met the inclusion criteria and consented for the study were recruited and randomized into study and control groups. The study group were placed on metformin 1000 mg daily and letrozole 7.5 mg daily from the second to the sixth day of the menstrual cycle, while the control group received letrozole 7.5 mg from the second day to the sixth day. Outcome measures recorded were ovulation, conception and pregnancy. The ovulation rate was 75.8% in metformin and letrozole group and 78.8% in letrozole alone group, conception rate was 42.4% and 33.3% respectively while pregnancy rate was 27.3% and 24.2% respectively. There was a higher ovulation rate in letrozole alone group than in combined letrozole and metformin, while conception rate and pregnancy rate was higher in the combined letrozole and metformin.