Natural cycle IUI involves the introduction of washed and concentrated motile sperm into the uterine cavity and near the tubal ostia hours before or after ovulation to enable more sperm to travel a shorter distance to reach the site of fertilization.  It requires the use of ovulation detection kits near the estimated time of ovulation or frequent visits to the hospital for tracking the development of the follicles (that contain eggs) with scans and ovulation triggers or semen production. It appears to be a more acceptable option of treatment compared to expectant management for couples with unexplained infertility and mild male factor infertility.

Ovulation induction aims to cause release of eggs by an ovulating women or increase the number of eggs released every month with the assumption that this increases the number of eggs available for fertilization or implantation, and by extension, the chance of pregnancy. It may be combined with IUI, especially in couples with normal sperm count and morphology (structure) but weak motility. Establishment of tubal patency and a normal uterine cavity is a pre-requisite. Ovulation induction can be achieved with oral medications (e.g. clomiphene citrate, tamoxifen, letrozole, and metformin) or by injections (gonadotropins FSH or hMG) This appears to increase the pregnancy rate per month among couples with unexplained infertility and mild male factors, especially when combined with IUI. It is more expensive than expectant management or natural cycle IUI and also requires frequent scans for tracking the development of follicles (that contain eggs) and ovulatory triggers, as well as semen production for insemination. However, many patients with unexplained infertility and mild male factor infertility are happier with this treatment than expectant management or natural cycle IUI because of its modest cost and good results

IVF involves controlled ovarian hyperstimulation (COH) with gonadotropins, oocyte collection, attempts at fertilization in the lab, and the transfer of the resultant embryo into the endometrium.

This method eliminates potential causes of infertility such as problems related to ovarian dysfunction, cervical factors, sperm and egg transport, sperm-egg binding, fertilization, and early embryo development, while mostly ultrasound-guided embryo transfer ensures that embryos are properly placed in the uterine cavity. In some cases, failure of fertilization may be overcome with intra-cytoplasmic sperm injection (ICSI). 

Even when good fertilization and early embryonic development are achieved, clinical pregnancy may not follow as a result of many more unknown causes, such as abnormalities of the chromosome or endometrial receptivity.

IVF is more effective than ovulation induction and IUI, especially for couples who have had previous unsuccessful treatments with other methods. The pregnancy rate per cycle in our center is 35–62%. For this reason, it is recommended to proceed with IVF after 3–4 unsuccessful cycles of clomiphene or gonadotropin ovulation induction with IUI. This success rate is dependent on many factors, especially the age of the female partner.