Intrauterine Insemination (IUI)

Intrauterine Insemination (IUI) is a fertility treatment which involves putting washed sperm directly into the uterus using a specialized catheter at time of ovulation. The purpose of IUI is to give sperm a head start. However, the sperm must still swim to and fertilize the egg on its own.

When to Consider IUI

IUI is a less expensive and less invasive option than IVF and may be used for:

  • Unexplained infertility
  • Women using donor sperm
  • A hostile cervical condition, including cervical mucus problems
  • Cervical scar tissue from past procedures which may hinder the sperms’ ability to enter the uterus
  • Situations where the male partner is unable to ejaculate into the vagina
  • Low sperm count and/or mobility. IUI is often recommended when total number of swimming sperm in a semen sample is between 5 and 20 million/mL. A normal sperm count is above 20 million/mL. Sperm counts below 5 million/mL usually require IVF and ICSI.

For IUI to work, you need at least one fallopian tube that is open and healthy. IUI is not recommended for women:

  • Who have a severe disease of the fallopian tubes
  • With a history of pelvic infections
  • With moderate to severe endometriosis


First, we do a thorough work up to rule out any obvious fertility problems. Then, we ask you to determine the time of ovulation by checking your urine at mid-cycle with an ovulation predictor kit. When the monitoring indicates that you are about to ovulate, you will return to the clinic the following day for your insemination.

If the timing of your ovulation is uncertain, we may do a second insemination. If you do not ovulate regularly or if your cycles are very unpredictable, we may ask you to take a medication to regulate ovulation and increase the number of eggs being ovulated.

There are three medication regimens typically used with IUI:

  • Clomiphene
  • Letrozole
  • Gonadotropin injections (also called superovulation or ovulation induction)

The actual insemination takes less than 5 minutes and should be simple and painless.


1. Follicles stimulated: If you are taking medication you will start it at the beginning of your period for a course of 5 days to stimulate the growth of two to three eggs to maturity.
2. Monitoring: We will monitor you to assess the rise of LH as the follicles grow. Because fertility drugs can produce multiple eggs, monitoring is also needed to reduce the risk of multiple births. We use blood tests to measure estrogen concentrations, and ultrasound to measure follicular development.
3. LH Surge: If you are on medication, we may inject the hormone hCG (human chorionic gonadotropin) to induce ovulation when at least two or three follicles are mature, if you don’t surge on your own. If you are ovulating naturally, the IUI procedure will be done 24-36 hours after the surge in LH hormone.

4. IUI performed: On the morning of ovulation, the sperm sample (either donor sperm or that provided by the male partner) is washed and concentrated. A catheter will then be used to insert the sperm high into the uterus. This process maximizes the number of sperm cells that are placed in the uterus, thus increasing the possibility of conception. The IUI procedure takes only a few minutes and involves minimal discomfort.

5. Pregnancy testing and early ultrasound monitoring are conducted at the appropriate times.

How Successful is IUI?

Success rates may reach as high as 20% per cycle depending on variables such as female age, the reason for infertility, and whether fertility drugs were used, among other variables.

While IUI is a less invasive and less expensive option, pregnancy rates from IUI are lower than those from IVF. If you do not become pregnant within the first three treatment cycles, we will discuss other treatment options with you.

What are the risks of IUI?

The chance of becoming pregnant with multiples is increased if you take fertility medication when having IUI. Some women experience some discomfort such as cramping and light bleeding from the cervix.