The effects of timing of intrauterine insemination in relation to ovulation and the number of inseminations on cycle pregnancy rate in common infertility etiologies.

Background: Controlled ovarian hyperstimulation with intrauterine insemination (COH/IUI) is an established tool in medically assisted conception for many infertility factors. However, the proper timing of IUI after hCG trigger and the frequency of IUI are still debated. We aimed to examine the association between the cycle pregnancy rate (CPR) and: (i) single IUI timed at 36 ± 2 h post-hCG (pre- or post-ovulation) (ii) the number of IUI (single or double) for pre-ovulatory cases both aims in male, anovulatory and unexplained infertility.