Intrauterine Insemination (IUI)

The most common method of artificial insemination is intrauterine insemination (IUI). This process as the name may elude, is a process where sperm is placed directly into the uterus. Unlike intravaginal insemination and intracervical insemination, IUI requires the washing of sperm before it can be delivered into to uterus. ^[6]

Sperm washing is a process that not only prevents adverse events within the female’s uterus; it also increases the ability of the sperm to fertilize the egg. Essentially, the washing of sperm removed the sperm from the ejaculated seminal fluid.^7,8 During an IUI procedure the sperm must be washed to remove the prostaglandins in the semen. Prostaglandins cause the contraction of the uterus and if not removed by sperm washing, may even cause uterine collapse. In addition to removing prostaglandins, sperm are selected against other sperm to select for sperm that are 90% motile. ^[7] Sperm washing techniques will vary from fertility clinic to fertility clinic but there are two main methods to sperm washing.

The first method uses centrifuge and dilution. The semen sample is spun down and sperm cells are collected. The second method employs the use of an additional media which is added to the top of the semen sample. Sperm that are motile swim out of the semen and into the new added media. [7] This technique is known as the “Swim Up” technique. Additionally, sperm can be sorted for gender. First introduced in 1989, the ability of selecting for gender has greatly advanced and scientist are able to select with 90% purity between female (XX) and male (XY) sperm. [9] One such method employs use of a high-speed flow cytometer that is able to sort sperms cell based on fluorescence labeling^{. [9]}

After the washing of sperm, it can then be introduced into the female uterus. Introduction of the sperm into the female uterus is typically done by using a long catheter often called a “tom cat”. After introduction into the uterus, the physician can place a cervical cap over the cervical opening to ensure that sperm does not escape from the uterus^{. [6]}

^[10]

_[11]

Intrauterine insemination is a procedure that can be pursued by couples who may experience fertility struggles. Good candidates for IUI include: [12]

• Cervical Infertility: Females who have a cervix that does not respond to monthly hormonal changes
• Male Infertility problems
• Males with a below average sperm count
• Males that possess sperm motility problems
• Males that possess irregular shaped sperm
• Semen Allergy: In rare cases, a female partner may be allergic to the contents in the semen of her partners sperm
• Unexplained Infertility

Similar to other artificial insemination techniques, timing is important for IUI to be successful. The women will want to have just ovulated before the procedure is done. Ovulation can be tracked by basal body temperatures or by fertility monitors. [13]