IUI, Intrauterine Insemination

The IUI Procedure

IUI involves placing specially prepared, concentrated, sperm from the husband, or a donor, directly into the uterus. This is a painless procedure done by inserting a small catheter in the vagina and passing it through the cervix.

One of the most important steps in the IUI procedure is sperm preparation and RCC’s andrology lab meets the highest quality standards. Unlike most commercial labs, our andrology lab determines the semen volume, concentration, motility, and progression. Sperm morphology using Kruger strict criteria is performed and helps assess the sperm’s ability to penetrate an egg. This helps predict if IUI will be successful or if more advanced treatments like IVF using ICSI are needed.

IUI usually requires the use of ovulation enhancing drugs, such as Clomid (clomiphene citrate) or Femara (letrozole) tablets, and/or FSH injections to improve the chance of pregnancy. These drugs increase the likelihood of good ovulation and usually increase the number of mature eggs. They can also increase progesterone production, which helps the lining of the uterus develop.

Two intrauterine inseminations done 24- 48 hours apart may be considered if ovulation timing has been unpredictable. Sometimes two or more IUI cycles are needed and one is done each month ovulation can be accurately predicted.


FSH IUI cycles require the use of human chorionic gonadotropin (hCG) to induce ovulation because ovulation is blocked by other drugs used in these cycles (Lupron, Antagon, etc.). IUI is usually done 36-40 hours after the hCG injection. FSH cycles have the highest pregnancy rates and should only be administered by an infertility specialist because there is a higher risk of multiple births. IUI cycles are closely monitored at RCC and if too many eggs develop, we can convert an IUI cycle to an IVF cycle, which lowers the risk of multiples.

IUI cycles combining oral medications with FSH injections offer excellent success rates with low multiple rates (<20% chance for twin and <2-3% chance for triplets). RCC’s IUI success rates are among the highest in the region equaling some programs IVF success rates.

Most fertility specialists agree that if IUI has not worked in 4-6 treatment cycles other therapies, such as IVF, should be tried. IVF yields higher success rates; however, the cost to achieve pregnancy with IUI is less. (See more information on the cost of IUI.)

When is IUI the Best Treatment Choice?

  • Cervical factor infertility – Prior cervical treatment for dysplasia (cryotherapy, laser of the cervix, LEEP, etc.) or poor cervical mucus production.
  • Lack of conception after trying drugs like Clomid.
  • Unexplained infertility.
  • Mild endometriosis.
  • Older women with good ovarian reserve.
  • Mild to moderate male infertility.(See Semen Analysis)
  • Male ejaculatory problems.
  • Use of frozen sperm.

The American Society for Reprodutive Medicine provides additional information on IUI at their website.