Intrauterine Insemination (IUI)
Your guide to success, comfort, and expert care.
What is Intrauterine insemination (IUI)?
Intrauterine insemination (IUI), also known as artificial insemination, is a fertility treatment that involves placing sperm inside the uterus to facilitate fertilization. The goal of IUI treatment is to increase the number of sperm that reach the fallopian tubes and subsequently increase the chance of fertilization.
IUI is less invasive and less expensive than other assisted reproductive technologies such as in vitro fertilization (IVF). It is often tried before proceeding to more complex procedures, especially in cases of unexplained infertility, mild male factor infertility, or when there are issues with cervical mucus. However, the success rates for IUI are generally lower than those for IVF and vary depending on the age of the woman and the underlying fertility issues.
The IUI Treatment Process
Ovulation Monitoring
The menstrual cycle is closely monitored to predict the timing of ovulation. This may involve the use of ovulation predictor kits, ultrasound, and/or blood tests to ensure the insemination is timed correctly with ovulation.
Semen Sample Preparation
On the day of the IUI, semen from a partner or a donor is taken and washed in a laboratory to separate the sperm from the seminal fluid. A concentrated amount of active, motile sperm is collected.
After the Procedure
The patient may rest for a short period after the insemination, but can carry on with normal daily activities. Some people may experience light spotting for a day or two after IUI.
Insemination Procedure
The insemination procedure is usually quick and relatively painless. A speculum is inserted into the vagina to keep the vaginal walls open. Using a thin, flexible tube (catheter), the washed sperm is then transferred directly into the uterus. This process is relatively quick and typically does not require any anesthesia.
Luteal Phase Support
Depending on the individual circumstances, the doctor may prescribe medications or hormones to support what is known as the luteal phase—the period between ovulation and the start of the period.
Pregnancy Test
About two weeks after the IUI, a pregnancy test can be done to determine if the procedure was successful.
Precision in Parenthood: IUI Success Starts with IVF1
Schedule a ConsultationPrecise IUI Timing for Success
The precise timing of Intrauterine Insemination (IUI) is crucial for its success and is more critical than with natural intercourse. This is because sperm deposited during intercourse are supported by the cervical mucous, which not only nourishes them but also allows them to be released gradually into the uterus over time. In contrast, sperm introduced through IUI are placed directly into the uterus and have a shorter lifespan within the female reproductive tract. Therefore, insemination must be carefully synchronized with ovulation.
To optimize the timing of IUI, one common approach is the use of an ovulation predictor kit, which detects the surge in luteinizing hormone (LH) typically 12-24 hours before ovulation. Upon a positive test result, usually checked with morning urine, IUI is then scheduled for the following day.
Alternatively, ovulation can be medically induced. When ultrasound monitoring shows that the eggs are sufficiently mature, an injection of the hormone hCG can be administered to trigger the release of the eggs. Ovulation generally occurs around 36 hours post-injection, and the IUI is then performed accordingly, typically two mornings after the hCG is given. This method allows for a more controlled and predictable timing for the insemination procedure.
Factors That Affect IUI Success
There are many factors that determine how successful an IUI procedure will be. Some of these are the same factors that apply to any fertility treatment: age of the female, ovarian function, fallopian tube blockage, pelvic adhesions, other additional causes of infertility, whether fertility medications were used, and more.
Amount of Motile Sperm
One important factor that is specific to intrauterine insemination is the amount of motile sperm that is inserted into the uterus. Several studies have indicated that if a there is a low number of progressively motile sperm after the sperm wash, the chance for pregnancy is lowered. The lower the number, the lower the chances for pregnancy. If there is a high percentage of abnormal sperm on a semen test, that will also lower the chances for success.
Optimized Timing
Timing of the intrauterine insemination is also very important. In order to maximize the chance for pregnancy, sperm must be inseminated on the same day as ovulation. Performing the IUI the day before or after will lower the chance for IUI success. It is not acceptable for a provider of intrauterine inseminations to tell a patient who is ovulating on a Sunday that they must wait until Monday when the office is open. This will severely compromise the chances for success.
Single Insemination
On the other hand, there does not seem to be any advantage to performing an intrauterine insemination twice. Several well done studies comparing the pregnancy rates between couples having a single insemination to those having two inseminations have found no significant difference in the pregnancy rates.
Additional IUI Information
It is not necessary to abstain from intercourse before an IUI. Sperm counts always vary, and the frequency of ejaculation does not have a consistent effect on sperm count. There may be more sperm on a second or third ejaculate at one time and at other times there may be less sperm.
Our recommendation is to have intercourse on the day that an ovulation kit turns positive or on the day that an hCG trigger injection is given. The IUI is then timed as indicated above.
The semen sample is collected through ejaculation into a sterile collection cup that we provide in the office. The specimen is usually collected in the office in a specially designated private room. A partner may be in the room to help with the collection. On occasion, an individual may be unable to collect a sperm specimen in the office. In those situations, we allow collection at home, but it is important to get the specimen to the office within a half hour and that it be kept warm. It is also possible to use a specialized nontoxic collection condom. However, ordinary condoms cannot be used for IUI.
We will schedule the semen collection approximately one hour before we schedule the IUI. This allows time for the sperm to liquefy in our incubator and to prepare for the IUI.
Before sperm can be placed into the uterus, it must be prepared. The fluid that is emitted upon ejaculation is composed of two main components: seminal fluid and sperm. Seminal fluid contains many types of hormones and chemicals. One group of chemicals in particular can cause problems and are known as prostaglandins.
Prostaglandins are responsible for many bodily functions. If high levels of certain types of prostaglandins are placed directly into the uterus, they can cause the individual to become very sick. The symptoms of prostaglandin absorption during intrauterine insemination – IUI, are nausea and vomiting, fever, diarrhea and cramping. The symptoms usually begin within a few minutes of performing the IUI.
Preparation for an IUI involves separation of the sperm from the seminal fluid and is known as a sperm wash. Sperm “wash” for IUI is actually a bad term because the sperm are not actually being washed or cleaned.
There are several methods for performing a sperm wash for an intrauterine insemination. The medical literature does not clearly indicate that any method is any better than any other. It is therefore up to the personal preference of the physician performing the IUI.
Once the semen is collected it must sit for a while to allow it to liquefy. The consistency of the semen will still be thick at this point. Next the semen is mixed with a chemical solution called sperm wash media. This solution is specially designed to not harm sperm. The semen and the media are thoroughly mixed.
Next, the semen and media mixture is placed into an instrument called a centrifuge. The centrifuge will rapidly spin the test tube containing the mixture. This causes the sperm to settle at the bottom in a small pellet. The fluid above the pellet contains the seminal fluid and can be poured out.
Finally, the sperm pellet is dissolved by adding some fresh sperm wash media and mixing thoroughly. The specimen is now ready for insemination.
During the IUI procedure at our clinic, the patient will experience a process similar to a routine pap smear. Once in the treatment room, the patient will be asked to undress from the waist down and use a drape sheet for privacy. Positioned on the examination table with feet in stirrups, a speculum is inserted into the vagina to facilitate the introduction of a washed sperm sample via a catheter and syringe directly into the uterus.
After the procedure, there is no specific requirement for rest, and the patient may resume normal activities immediately, including returning to work or engaging in exercise. Couples are also advised that it is safe to have intercourse following the procedure, which can be particularly beneficial for those with very low sperm counts, as it can increase the total sperm count in the uterus and potentially enhance the chances of pregnancy.
It is not uncommon for the patient to notice some fluid leakage after the insemination, which can be due to the semen refluxing through the cervix or minor uterine contractions expelling some of the fluid. This should not cause concern, as sufficient sperm typically remains within the uterus to enable pregnancy. Resting afterward to prevent reflux is not necessary, as it does not impact the success of the procedure.
Sometimes, it will be difficult to pass the IUI catheter all the way into the uterus. There are several ways around this problem.
First, there are IUI catheters that contain a flexible wire inside. This wire allows the physician to bend the catheter into a shape that will follow the path of the cervix more easily. It also gives more rigidity to the catheter, which is normally very soft and floppy. Often, this is all that is needed for the IUI catheter to reach the uterus.
In other cases, an instrument called a tenaculum can be used to manipulate the cervix. The physician performing the insemination can tug on the cervix to straighten the angle between the cervix and uterus, thus making it easier to pass the IUI catheter through to the uterus. Having the patient fill her bladder before the procedure can also help straighten the angle.
Finally, ultrasound can be used to help the physician guide the catheter into the uterine cavity.
An IUI generally does not cause much discomfort. Most patients say that they experienced the same level of discomfort as a pap smear. There can be some cramping afterward, but most of what is felt is likely due to ovulation.
The use of IUI appears to improve chances of pregnancy when combined with either clomiphene citrate (CC) or gonadotropins such as Gonal F or Follistim. But does IUI increase the chance for pregnancy if used without fertility drugs? Unfortunately, there isn’t much research that has looked into this.
The best type of study is called a randomized controlled trial. In couples with unexplained infertility, IUI alone has been evaluated against intercourse in just one randomized trial. In this study, couples with unexplained infertility were split into one of two groups. One group was treated with IUI at the time of ovulation. The second group used intercourse alone at the time of ovulation. Conceptions occurred in 6 of 145 (4.1%) IUI cycles and 3 of 123 (2.4%) intercourse cycles. This is not a statistically significant finding, meaning that the variation in conception rates could have been a matter of chance.
Another trial compared IUI with intracervical insemination (ICI). The study was not ideal for the evaluation of unexplained infertility, as 25% of male partners had low sperm counts. The majority of patients had unexplained infertility; pregnancies occurred in 35 of 717 (4.9%) IUI cycles and 14 of 706 (2.0%) ICI cycles.
Combining the numbers from the two trials gives a rate of 4.76% with IUI and 2.05% with controls, and the absolute treatment effect was 4.76 minus 2.05 or 2.71. Thus, one would need to provide 100/2.71 or 37 cycles of IUI therapy to obtain a single additional pregnancy compared with control cycles.
In summary, based on these two trials, there is a significant but small effect of IUI therapy: 1 additional pregnancy in 37 IUI cycles compared with control cycles.