The introduction of the sperm sample into the uterine cavity may be performed to increase the number of sperm in the upper genital tract. In certain individuals this may increase the likelihood of conception. IUI bypasses cervical and vaginal factors preventing sperm entry into the uterus. In cases with borderline semen parameters, we are able to compensate for male factor infertility. In cases of severe male factor infertility, ICSI may be advised and is ultimately more cost effective despite the higher cost of IVF. Intrauterine insemination is sometimes called artificial insemination or therapeutic sperm insemination.
In order to introduce the sperm into the uterine cavity the semen has to be treated to remove chemicals in the liquid portion of the semen which may cause irritation of the uterus. The washing procedure takes about 2 hours. Sperm samples are most often collected in the clinic to assure a prompt delivery to the lab. Once in the lab, the specimen will be allowed to liquefy. Different types of special liquids called sperm media are used to rinse the debris and chemicals from the semen. The concentrated mixture that remains is made mostly of sperm. Gradient washes are often done to improve the concentration and selection of motile sperm. The washed sperm is now safe and ready for insertion into the uterus.
The insemination is a relatively simple procedure similar to obtaining a Pap smear, which can be accomplished in the clinic without anesthesia. A small plastic catheter (tube) is used to insert the specimen into the uterine cavity through the cervix. A small amount of leakage and/or spotting may occur after the procedure. This does not reduce the effectiveness of the technique. Once the procedure is completed there is no limitation of activity. There is no benefit from lying flat after the IUI procedure despite common myths.
The procedure is done only once per cycle because the time of ovulation can be accurately predicted and the insemination can be timed to coincide with the release of the eggs. Once inside the uterus, the sperm will rapidly disperse throughout the reproductive tract. Surface tension and motion from the fallopian tubes help with this process.