The aim: A prospective randomized comparative study was conducted to investigate the effect of dual trigger, using gonadotropin releasing hormone agonist with human chorionic gonadotropin (hCG) versus hCG alone, for ovulation trigger in controlled ovarian stimulation intrauterine insemination (IUI) cycle on pregnancy outcome. Materials and methods: Ninety women were randomly allocated into equal groups to trigger ovulation for IUI cycle using either method; IUI was performed following 36-42 hours post triggering. Luteinizing hormone (LH) and progesterone levels were measured at insemination day. Results: The baseline of demographic and clinical characteristics of both groups was similar. Progesterone level was higher in dual trigger group than in hCG alone group (1.61 versus 0.71 ng/mL, P≤0.0001); while LH level was lower in dual trigger group (19.35 versus 24.51 IU/L, P≤0.014). Furthermore, LH level at the day of IUI was higher in pregnant women than in non-pregnant (27.9 versus 20 IU/L, P≤0.007). Conclusions: Pregnancy rate was equivalent in both groups. More intensive investigation is required to study the efficacy of the dual trigger in IUI cycle.