It was randomised controlled study to compare the efficacy of clomiphene and letrozole in polycystic ovarian syndrome(PCOS) women with infertility.The aim was to select more appropriate treatment for ovulation induction in PCOS women.

The prevalence of infertility due to polycystic ovarian syndrome in Pakistan is 21.9%.It leads to an ovulation which results in infertility.The objective of this study was to compare the efficacy of letrozole vs clomiphene citrate for ovulation induction in PCOS women.Methods.It was a randomised controlled trial conducted in department of gynaecology and obstetrics ,Services Hospital Lahore from 2016-2019.

Total 230 patients were included in study, they were divided in two groups, out of which 220 patients were analysed. .Group-A patients were given clomiphene citrate 50-150mg per day for 5 days starting from 2nd day of menses and group B patients were given letrozole 2.5-7.5mg per day for 5 days. Transvaginal ultrasound monitoring done from day 10-12 of menstrual cycle to measure follicle number and size.When follicle achieved a diameter of 18-20mm, then Inj HCG(human chorionic gonadotropin)10,000 IU intramuscular was given. Ovulation was confirmed by day 21 S.progesterone. When patient conceived, they were followed up till delivery.

Inclusion Criteria:

• Women age between 18-40 years.
• Normal husband semen analysis.

Exclusion Criteria:

• All infertile couples who had other causes of infertility than PCOS.
• Those who had recently taken these medications.
• Any contraindication to use of drugs e.g renal or hepatic dysfunction, hypersensitivity to this drug.
• BMI>35 because obese women respond poorly to ovulation induction.

Two treatment groups were made by random computer generated number i.e. Group A and Group B. Two Concealed boxes labelling A and B containing study drugs were made by pharmacist.Then participants were given drug from concealed boxes according to computer generated number.