What Are the Chances of IUI Success on the First Try?

Intrauterine insemination or IUI is an artificial reproduction technique that involves inserting sperm that have been “washed” in a laboratory and injected into a woman’s uterus. Ideally, this can result in conception if a couple has been experiencing fertility issues related to sperm quality or other infertility causes. While IUI can increase the likelihood a woman will get pregnant, the chances of IUI success on the first try are not 100 percent. In this article, you can read the likelihood of success for women who try to conceive with IUI versus women attempting to conceive naturally.

IUI success on the first try

How Does IUI Work?

IUI involves conducting testing to determine when a woman is ovulating, as this is the only time of the month that she can become pregnant. Sometimes, a fertility doctor will recommend taking medications that will boost ovulation and fertility if they believe this will increase a woman’s success of becoming pregnant. When it is determined that a woman is getting ready to ovulate, the woman’s partner will donate his sperm. This sperm is then taken to a laboratory where it is prepared or “washed.” This process involves applying chemicals that help to separate the highest-quality semen while also removing proteins that could potentially cause allergic reactions or cramping in a woman trying to get pregnant.

When a woman is officially ovulating, she will go to her doctor’s office for the IUI process. A doctor will use a special long, thin instrument known as a catheter that is inserted into her vagina, through her cervix, and into the uterus. The doctor will then inject the prepared semen into the uterus. A woman will usually wait somewhere between 45 minutes and an hour before getting up and leaving to return to her daily activities. The procedure is not associated with many side effects although cramping and some spotting can occur.

Sometimes a doctor will have a woman return the following day for an additional IUI procedure. This can increase her chances for becoming pregnant. Ideally, the procedure will be effective and she will become pregnant.

A Look at IUI Success Rates

There is a wide variety of available data available regarding IUI success rates. Because IUI depends upon selecting the right patient, there are many issues that can come into play when considering IUI and its success rates.

Overall Success Rates

Looking at all couples who use IUI as an assisted reproduction treatment, the likelihood for pregnancy is about 20 percent per cycle, according to the American Pregnancy Association. However, these success rates depend upon many variables, especially a woman’s age, infertility causes (if they are known), and whether or not she is using fertility drugs to conceive.

Sperm Morphology

One consideration to make regarding IUI success rates is the man’s sperm morphology. Sperm that are not shaped as is expected may not be able to swim to and/or penetrate the egg for fertilization. As a result, many fertility clinics will recommend conducting a semen analysis to determine if a man’s sperm county, motility, or morphology (sperm shape) is affecting conception. According to RESOLVE, the National Infertility Association, the chances of conception using IUI with affected sperm morphology are as follows:

  • Under age 35 with sperm morphology greater than 5 percent: The chances of conceiving when greater than 5 percent of a man’s sperm is of normal morphology is about 13 percent for women ages 35 and under.
  • Under age 35 with sperm morphology less than 5 percent: The chances of conceiving when less than 5 percent of a man’s sperm is normally shaped is 7 percent.
  • Over age 35 with affected sperm morphology: Pregnancy rates are zero for men whose sperm morphology is less than 5 percent. As a result, most doctors will recommend using in vitro fertilization as an assisted reproduction technology in women older than ages 35.

Facts on Natural Conception Rates

Just as conception rates for IUI depend on a woman’s age, so do conception rates for women who are trying to get pregnant by having unprotected sex without taking fertility medications. According to a journal article published in PLos One, the likelihood of becoming pregnant via unprotected sex include:

  • Women age 25 who have been trying for three months: The likelihood of getting pregnant on their next menstrual cycle is 18 percent.
  • Women age 40 who are trying to get pregnant for three months: The likelihood of getting pregnant on their next menstrual cycle is 7 percent.
  • Women age 25 who have been trying to get pregnant for one year: The likelihood of getting pregnant on their next menstrual cycle is 10 percent.
  • Women age 40 who have been trying to get pregnant for one year: The likelihood of getting pregnant on their next menstrual cycle is 3 percent.

Conclusions on If the IUI Success Rates on the First Try

The IUI process has helped women across the United States successfully conceive. However, its success rates tend to be lower than that of in vitro fertilization and are often dependent upon why a couple is experiencing infertility concerns. For example, those who have infertility related to a man’s sperm morphology may experience greater success rates if more than 5 percent of his sperm is functioning normally. There are some situations in which IUI is not likely to work at all, such as when a woman is older than age 35 and her partner has affected sperm morphology, if a women has endometriosis, and/or if a woman has experienced damage to her Fallopian tubes.

It’s important that a couple discuss their infertility concerns with their fertility doctor. They should discuss all assisted reproduction technology treatment options to determine the ones that will be most effective for them. If IUI does not prove effective after several cycles, the couple may wish to try other methods for conceiving.


American Pregnancy: Intrauterine Insemination (IUI)

Human Fertilization & Embryology Authority: What Is Intrauterine Insemination and How Does It Work?

Mayo Clinic: Intrauterine Insemination (IUI)

PLos One: Time to Pregnancy: A Computational Method for Using the Duration of Non-Conception for Predicting Conception

RESOLVE: Intrauterine Insemination: Will It Help Me Conceive?

WebMD: Infertility and Artificial Insemination