What is intrauterine insemination (IUI)? | Progyny

Updated by the Progyny Editorial Team. Reviewed by the Progyny Clinical Team - December 2025.

Intrauterine insemination (IUI) is a fertility treatment in which sperm is placed directly in the uterus to help increase the chance of pregnancy. You may have heard it called artificial insemination.

IUI is timed with your menstrual cycle so that sperm is placed at the time when the ovary releases an egg (ovulation). Sometimes, medicine is used to help mature and release the eggs to improve the chances of pregnancy.

Who might consider IUI?

IUI may be recommended for:

• People with unexplained infertility (no clear cause found after testing)
• Male infertility (such as mild to moderately decreased sperm count or motility)
• People using donor sperm (same-sex couples or single parents)
• Other specific causes of infertility such endometriosis, polycystic ovary syndrome (PCOS), problems with the cervix, problems with ovulation, or other medical reasons

Your healthcare team will review your medical history and test results to make sure IUI is a good option for you. This may involve blood tests, ultrasounds, and a semen analysis.

How does IUI work?

There are 2 main cycle options with IUI. Your team will walk you through the details, what to expect, and what's best for you.

• In a natural cycle, the procedure is timed based on your body's ovulation.
• In a medicated cycle, you'll take fertility medicine. Starting around day 2 or 3 of your cycle, you may take oral medicine (such as clomiphene citrate [Clomid] or letrozole [Femara]) for 5 to 7 days to help your ovaries mature eggs.

Timing is important

With either cycle option, you'll need to know when you ovulate. Ovulation is often around day 11 or 12, but it can vary. Your doctor may recommend that you track ovulation using:

• An ovulation predictor kit, which is a urine test that detects an LH surge (LH is a hormone that surges before an egg is released).
• An ultrasound that will show images of the ovaries and egg growth.
• A blood test which will check hormone levels.

When the egg is mature, you may be given a trigger shot of human chorionic gonadotropin (hCG). This medicine helps make sure the egg is released at the right time. A trigger shot can be used in both natural and medicated cycles.

The IUI procedure

A day or two after your LH surge or trigger shot, it's time for the IUI procedure.

If using fresh partner sperm, your partner will need to come to the doctor's office with you to give a semen sample. They may be asked to avoid ejaculating for 1 to 2 days before the procedure. Or sometimes, your provider may recommend intercourse in the days leading up to the IUI.

What happens during an IUI?

1. Semen is prepared using a process called "sperm washing" to isolate the highest quality sperm. The prepared sample is placed in a syringe connected to a catheter (thin tube).
2. You'll lie on an exam table, similar to a Pap smear. A speculum is placed in the vagina and the catheter is inserted through the cervix into the uterus to release the sperm close to the egg. This usually only takes a few minutes, though it may take longer for some people (like if you've had a C-section or abdominal surgery like a myomectomy).
3. You'll rest briefly, and then you can go about your day. You may have light spotting or cramping for a day or two. Call your doctor if you have heavy bleeding, pain, or fever.

Pregnancy results, success rates, and risks

You can take an at-home pregnancy test about 2 weeks after the IUI. Testing too early can give inaccurate results.

Success rates vary based on your age and health history.

• For people under 35, the success rate is about 10% to 15% per cycle.
• For people over 40, the rate is lower, about 1% to 4% per cycle.

With medicated IUI, there is a risk of multiple pregnancy (twins or more).

• With oral medicine (Clomid or letrozole), the risk of twins is about 5% to 10%.
• With injectable medicine (gonadotropins), the risk of multiples is 20% to 30%. This medicine is not recommended by expert guidelines for most people.

Talk to your healthcare team to see if IUI is a good option for you and your family-building goals. Your Progyny Care Advocate is here to support you every step of the way.

Disclaimer: The information provided by Progyny is for educational purposes only and is not medical advice. Always consult a qualified healthcare provider for medical guidance.