NCT02703649.

Methods	A prospective randomised clinical trial
Participants	PCOS patients who require induction of ovulation will prospectively randomised into two groups
Interventions	Single 20 mg dose of Letrozole on day 3 of the menstrual cycle. Monitoring for response will include the usual measurements of serum Estradiol (E2), FSH, LH, progesterone and transvaginal ultrasound for follicular count and endometrial thickness measurement. First monitoring will be on day 7 of the cycle and the rest of the monitoring will be determined according to response. Daily dose of Letrozole 2.5 mg starting day 3 for 5 days. Monitoring for response will include serum estradiol, FSH, LH, progesterone and transvaginal ultrasound for follicular count and endometrial thickness measurement. First day of monitoring will be on day 7 and the rest of monitoring will be determined according to response.
Outcomes	Primary outcomes: Comparison of the number of follicle > 15 mm at day of ovulation Secondary outcomes: Pregnancy rate Comparison between the two groups Estradiol levels at day of ovulation triggering OHSS Clinical pregnancy rate
Notes	Estimated trial completion date 2018, no data available; author has been contacted, no response