- The study will be conducted on women with fertility difficulties who are designated for intrauterine insemination treatment (IUI). The research sample size is 137 treatment cycles per group (total of 274 treatment cycles). The women will be randomly divided into two groups. Some will undergo the standard bolus IUI treatment and others will be treated with the EVIE Slow Release Insemination method (SRI). Women who fail to conceive in the first treatment will next receive the alternative treatment. This means that a woman treated with the IUI method who does not become pregnant will then be treated with SRI, and vice versa (crossover method). The study will include women treated with Clomiphene Citrate or with other Gonadotropin-based treatment. Every couple treated will undergo at least 2 insemination cycles (unless pregnancy has already been achieved).