Reproductive Assistance: What Is Intrauterine Insemination?

What Is It?

Intrauterine insemination, or IUI, is a common form of artificial insemination (AI). (AI refers to techniques used to introduce sperm into a woman’s body through means other than sexual intercourse.) IUI is relatively less invasive than some other assisted reproductive technology (ART), which is one of the reasons that physicians often will offer IUI as a treatment before IVF and other techniques.

IUI is performed in a series of steps:

  • A woman’s cycle is, with or without medication, monitored so that her time of ovulation is apparent.
  • A sperm sample is obtained from either the male partner or donor. The sample has optimally been through a process referred to as “sperm washing”.
  • Sperm sample is then inserted into woman’s uterus via a catheter through her cervix.

The goal is to place as many active, well-formed sperm as close to the ovulated egg as possible, thereby increasing their chances of meeting.

Who Benefits From It?

In general, IUI is helpful to those seeking conception but who have:

  • Unexplained infertility
  • Some cases of endometriosis
  • Some cases of male-factor infertility, such as low sperm count or decreased motility, poor ejaculation
  • Cervical mucus problems, such as sperm antibodies
  • Immunologic infertility

Accordingly, there are those who will probably not benefit from IUI, including cases of:

  • Structural infertility, such as that caused by severe tubal or uterine damage or blockage
  • Ovulatory dysfunction which does not respond to fertility medications
  • Severe sperm dysfunction

What Are The Stats?

Because of improved techniques, “pregnancy rates with IUI now approach those of normal fertile couples”, according to Dr. Jerome H. Check, Medical Director of the Cooper Center for In Vitro Fertilization, P.C.

A study in the January 21, 1999 New England Journal of Medicine demonstrated that while IUI is effective (18% pregnancy rate), IUI combined with super-ovulation (using fertility drugs) results in the highest rate of pregnancy (33%). Readers should note that in this study of 932 couples, the women had no identifiable infertility factors and the men had motile (referring to movement ability) sperm. The authors concluded that treatment with induction of super-ovulation and intrauterine insemination is twice as likely to result in pregnancy as is intrauterine insemination alone. (N Engl J Med 1999;340:177-83.).

Another report compared pregnancy rates resulting from timed intercourse or IUI, all with the use of gonadotropins. Published in the March 1998 issue of Fertility & Sterility, the meta-analysis of seven previously conducted studies involving a total of 980 cycles concluded “a patient’s chances of becoming pregnant are greater with IUI with her husband’s sperm than with timed intercourse in cycles superovulated with gonadotropins.” Gonadotropins are those fertility meds made of or simulating FSH, LH, or hCG, such as Fertinex, Repronex, Pergonal, Humegon, and others.

Specifically regarding the use of IUI in cases of male-factor infertility, it should be noted that one study found the “sperm quality that is necessary for successful IUI is lower than World Health Organization threshold values for normal sperm. Intrauterine insemination is effective therapy for male factor infertility when initial sperm motility is 30% and the total motile sperm count is 5 × 106. When initial values are lower, IUI has little chance of success.”

IUI is relatively inexpensive as compared to some other forms of ART. In a retrospective analysis of 45 previously published reports comparing the efficacy of a variety of infertility treatments, taking into consideration their success rates, it was determined that clomiphene citrate (CC) plus IUI is a cost-effective treatment for unexplained infertility. Failing that treatment, the researchers suggest hMG plus IUI is an efficacious therapeutic option. The estimated cost per pregnancy was $10,000 for CC plus IUI, $17,000 for hMG plus IUI, and $50,000 for IVF. Combined and adjusted clinical pregnancy rates for the methods observed were:

  • no treatment = 1.3% – 4.1%;
  • IUI = 3.8%;
  • CC = 5.6%;
  • CC + IUI = 8.3%;
  • hMG = 7.7%;
  • hMG + IUI = 17.1%;
  • IVF = 20.7%;
  • GIFT = 27.0%.

This study is particularly helpful for those who have unexplained infertility and therefore may not want to go the extremes of ART such as IVF.

Another report on the costs of ART concluded that in the absence of tubal blockage and severe male factor, “the most cost-effective approach is to start with IUI or super-ovulation treatments before resorting to IVF procedures.”