Intrauterine insemination (or IUI) is an in-office procedure that attempts to increase the likelihood of pregnancy by bringing the sperm closer to the egg in order for fertilization to occur. It has to be done at the right time in order to be effective, and as a result intrauterine inseminations should be timed to spontaneous (i.e. LH surge) or induced ovulation using human chorionic gonadotropin (i.e. HCG). An IUI should be performed the day after detection of the LH surge, because the oocyte (i.e. egg) has a limited window after its release to be successfully fertilized, and 34-40 hours after ovulation is triggered by HCG.
Intrauterine insemination is commonly used to treat mild male factor infertility, endometriosis, unexplained infertility, ovulatory dysfunction, and cervical factor infertility. It is also a viable treatment option for women under age thirty-eight and for couples who have failed multiple ovulation or superovulation induction cycles (usually 3-4 treatment cycles) before moving on to in vitro fertilization (IVF). Although intrauterine insemination is often seen as a step before IVF, pregnancy rates achieved with IUIs have not significantly increased over time (as they have with IVF) and as a result the number of intrauterine inseminations being performed is starting to decline.
Some have even advocated doing two inseminations instead of one at 12 and 36 hours after a HCG- induced ovulation to increase pregnancy rates associated with IUIs. However, studies have not shown a significant increase in pregnancy rates doing two inseminations. As a result, I encourage my patients to only do a single insemination during their treatment cycle because a second insemination is more associated with increased costs than the expected outcome.
“When should one look into other treatment options when intrauterine inseminations have failed?”
When should one look into other treatment options when intrauterine inseminations have failed? This is more dependent on female age, other infertility diagnoses, duration of infertility, and quality of the insemination specimen. I generally recommend in vitro fertilization if the female partner is over age 38 or has a history of diminished ovarian reserve because success rates with IVF is significantly higher than those achieved with intrauterine inseminations. I also recommend IVF after three or four failed intrauterine insemination cycles, because pregnancy rates begin to decline after the fourth IUI attempt. Studies have shown that after 4-6 insemination cycles pregnancy rates decline by half to two-thirds.
In all, intrauterine insemination is a viable treatment option for certain infertile couples. It can be an effective treatment for the right candidate, but it is starting to grow out-of-favor because of the shorter time to conception and increased pregnancy rates seen with in vitro fertilization.