The Impact of Intrauterine Insemination Timing on Pregnancy Outcomes in Unexplained Infertility

Objective: Currently, there is no consensus on the timing of intrauterine insemination (IUI).The aim of this study is to compare whether simultaneous, 24 hours later, or 36 hours later IUI after triggering with human chorionic gonadotropin (hCG) following ovulation induction influences clinical pregnancy outcomes. Methods:This randomized controlled prospective study was conducted between December 2017 and December 2018 with 123 patients who applied to the infertility clinic for pregnancy demand and underwent IUI.All patients underwent basal ovarian testing and transvaginal ultrasonography for infertility assessment on days 2-4 of menstruation, hysterosalpingography (HSG) performed in the follicular phase, and semen analysis after 3-5 days of abstinence.Patients were categorized into three groups based on IUI timing, ensuring it did not fall on a weekend.Group 1 consisted of patients who underwent IUI on the same day as hCG-triggered ovulation, Group 2 included those who underwent IUI 24 hours after hCG trigger, and Group 3 comprised patients who underwent IUI 36 hours after hCG trigger.Results: Data from 123 patients meeting the study criteria and a total of 198 cycles were analyzed.IUI was performed simultaneously with trigger in 48 cycles, 24 hours after trigger in 66 cycles, and 36 hours after trigger in 84 cycles.A total of 29 pregnancies (14.6%) were achieved out of 198 cycles, with a pregnancy success rate of 23.5% per patient.In Group 1, 9 pregnancies (18.8%) were achieved in 48 cycles, 9 pregnancies (13.6%) in Group 2 out of 66 cycles, and 11 pregnancies (13.1%) in Group 3 out of 84 cycles.There was no statistically significant difference in pregnancy success rates among the groups based on IUI timing after trigger (p=0.65). Conclusion:There was no statistically significant effect of performing IUI simultaneously, 24 hours later, or 36 hours later after hCG trigger on clinical pregnancy outcomes.