For women with anti-sperm antibodies in their cervical mucus or “poor” mucus and for men with mild male factor infertility, intrauterine insemination (IUI) is a common first-line fertility treatment where washed and concentrated sperm are placed directly into the uterus to maximize the chances of fertilization.

IUI is typically performed in women receiving ovarian stimulation with clomiphene citrate or follicle-stimulating hormone (FSH). These treatments require close monitoring with ultrasound, estradiol levels, and physical examination to optimize the chances of pregnancy and to avoid hyperstimulation and multiple pregnancies.

Intrauterine Insemination (IUI)

Intrauterine insemination (IUI) is commonly performed in couples whose infertility investigations have failed to detect a specific cause of infertility (unexplained infertility) or have shown mild male factor infertility. It is also used for therapeutic donor insemination. The procedure involves the placement of prepared (“washed”) sperm into the female partner’s uterus using a small sterile catheter (fig 1).

In order for insemination to be successful, it must be performed prior to ovulation of the egg. To detect ovulation, urine ovulation predictor kits (OPK) are recommended, which detect the LH surge. These kits are available at PCRM as well as most pharmacies without a prescription. Electronic fertility computers/monitors are not recommended while using fertility medication as the higher hormone levels may give a false reading.

The insemination procedure itself requires a visit to the clinic by both partners. During the week, the male partner is required to produce a sperm sample around noon on the day of insemination, with the IUI occurring around 2 pm that afternoon. On weekends and holidays, the sample collection and IUI are performed in the morning. The insemination is typically performed by the nursing staff and is similar to having a Pap test. It is typically little or no discomfort experienced during the IUI procedure.

Generally, insemination is done each month until pregnancy is achieved or sufficient inseminations have been done to suggest that alternative treatments may be necessary. We will recommend a consultation with your physician after 3-4 inseminations have been completed to evaluate your treatment plan. For various reasons (e.g. vacations, illness) it may not be possible for you to have consecutive inseminations performed. This is not a problem and does not affect your chances of success.

The overall pregnancy rate with superovulation (production of more than one egg) and IUI is 10-20%, with a multiple pregnancy rate of 20-30%. This rate may appear low but is considerably higher than if the couple continued on their own. Your physician will discuss your individual situation and help you to understand your chances for success and treatment options. For couples with infertility, the pregnancy rate with IUI without medication is not higher than simply timing intercourse, so medication will traditionally be recommended.

Figure 1: Intrauterine insemination (IUI)
Figure 1

Superovulation IUI

Superovulation, or Controlled Ovarian Hyperstimulation (COH), combined with IUI has been demonstrated to be an effective method of treatment for couples where less invasive therapies have not been successful in achieving a pregnancy. The goal of superovulation is to increase both the number of eggs released (3-4 per cycle) to help offset the normal age-related decline in egg quality, that all patients experience to a certain degree. Multiple eggs are generated with the administration of follicle-stimulating hormone (FSH), which is the same hormone that the woman’s brain naturally produces to make eggs. Given the potential for the production of an excessive number of eggs, patients doing this treatment require close supervision through a fertility centre, to monitor ovarian follicle (contain the eggs) numbers and estradiol levels. Once the follicles have reached the optimum size (18-20 mm), an injection of a hormone called hCG is given to cause or “trigger” ovulation. HCG is in fact the pregnancy hormone but very similar to the hormone that is naturally released from the brain to cause ovulation. Intrauterine inseminations are typically performed 24 to 36 hours later. HCG is the pregnancy hormone, but structurally very similar to the hormone that causes ovulation naturally, luteinizing hormone (LH). IUI is always recommended when doing superovulation as this has been shown to optimize the likelihood of conception.

The most common side effects with superovulation are lower abdominal fullness and bloating. The most significant risks are high-order multiple pregnancies and ovarian hyperstimulation syndrome. The majority of multiple pregnancies are twins; however, more than two fetuses can sometimes develop. The risk of high-order multiples is actually greater with superovulation cycles compared to IVF, since the number of eggs ovulated cannot be precisely controlled, unlike IVF where eggs are retrieved and a select number of embryos are replaced.

Frequently Asked Questions

What is IUI’s success rate?

Studies have demonstrated that infertile couples treated with IUI will at least double their chances of conception when compared to timed intercourse or intracervical insemination.

Do I need to take medications with my IUI treatment?

Frequently, the IUI procedure is performed in combination with ovulation induction. This may be done using an oral medication called clomiphene citrate or with daily injections of gonadotropins (follicle-stimulating hormone [FSH]).

How does IUI increase my chance of pregnancy?

The IUI procedure works by concentrating the healthiest sperm in the ejaculate and placing the “washed” sperm into the uterus adjacent to the fallopian tube. This bypasses any potential cervical factor problems and removes the sperm that are less likely to fertilize the egg.