Objectives: To determine the factors predicting pregnancy in patients undergoing controlled ovarian hyperstimulation with intrauterine insemination. Study design: Prospective obsservational study Population: All subfertile women attending our hospital from january 2016 till july 2016 undergoing stimulated IUI cycles were recruited to the study. Main outcome: Positive urine pregnancy test was the main outcome measured. Predictive factors evaluated were female age, FSH/LH ratio, day 3 LH values, endometrial thickness, number of follicles developed and post wash total motile sperm count. Methods: All women participating in this study underwent ovulation induction with clomiphene citrate/FSH injection. Follicular monitoring was done from day 9 of cycle. Ovulation trigger with injection hCG 10,000 units was given when the follicle size was more than 18mm. Intrauterine insemination was done 36 hrs later. Luteal phase support with vaginal progesterone was given for the next 25 days. Urine pregnancy test was performed 25 days after IUI. A maximum of three cycles of IUI was given to each woman. Results: A total of 296 women underwent 358 stimulated IUI cycles. The overall pregnancy rate was 9.21%. The pregnancy rate was higher in the group where in the age was between 20 to 30 years, FSH/LH ratio was less than 2, day 3 LH value of less than 5, post wash sperm count of more than ten million, with monofollicular development and endometrial thickness of more than 7mm. On binary logistic regression using multivariate analysis only post wash sperm count of more than ten million and monofollicular development had a significant p value in predicting pregnancy. Conclusion:.Intrauterine insemination can be given as an effective treatment option for the subfertile couple with mild male factor infertility. Monofollicular development should be the aim in stimulated IUI cycles with regard to the success and patients’ safety.