GLOSSARY

Intrauterine insemination (IUI)

Intrauterine insemination (IUI) is a type of artificial insemination used to address infertility or use donor sperm. With this procedure, sperm is injected directly inside the uterus, helping it get closer to the egg to fertilize. Intrauterine insemination is done during ovulation to increase the chances of achieving pregnancy. 

What is intrauterine insemination (IUI)?

Intrauterine insemination (IUI) is a type of artificial insemination procedure in which sperm are inserted directly into the uterus during ovulation to facilitate fertilization. By washing and concentrating the sperm and eliminating some obstacles on the path to the egg, IUI can improve the chances of pregnancy for some couples. IUI may be used for a number of reasons, including achieving pregnancy with donor or frozen sperm, helping those with male- or female-factor infertility, or assisting those with semen allergies.

Process of intrauterine insemination (IUI)

The menstrual cycle of the birthing person will be monitored to determine the best timing for the IUI process, which should happen at the time of or just before ovulation. In cases of ovulation disorder, such as PCOS, a fertility specialist physician may prescribe medication to induce ovulation before an IUI. This ensures that the female patient will have an egg ready to ovulate when the insemination is performed.

Before the IUI procedure, a semen sample must be provided. Either fresh or frozen sperm can be used. The semen will undergo a process called sperm washing, in which the proteins of the semen are removed and healthy sperm is concentrated.

During the IUI procedure, the doctor will insert the concentrated sperm directly into the uterus with a catheter. The procedure takes about 10 minutes. If the sperm successfully fertilizes the egg, and the fertilized egg develops properly and implants in the uterine lining, pregnancy is achieved.

Intrauterine insemination (IUI) and male fertility

IUI can help achieve pregnancy in cases of mild to moderate forms of male infertility. This includes impaired sperm quality, like low sperm motility. By bypassing the cervix, sperm have a shorter distance to travel to reach the egg, which can be helpful when sperm swim slowly or less effectively. Research shows that success rates with IUI are highest when 14% or more of the sperm have normal morphology and 30% or more are motile.

What about IUI for low sperm count? Some studies suggest that IUI is a reasonable first-line treatment plan if total motile sperm count (TMSC) is greater than 10 million, while other studies indicate a lower threshold of greater than 5 million. Those with very low sperm count or severe male-factor infertility may move directly to in vitro fertilization (IVF).

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