Intrauterine Insemination (IUI)
Common Indicators for IUI
IUI is often recommended for patients diagnosed with unexplained infertility, mild male factor infertility, cervical issues, or irregular or absent ovulation, making them strong candidates for this treatment.
The primary goal of IUI is to increase the number of sperm that reach the Fallopian tube, thereby enhancing the chances of fertilization. IUI gives the sperm a head start by placing it closer to the egg, but the sperm still needs to reach and fertilize the egg on its own. Depending on your specific fertility diagnosis, IUI may be timed with your natural cycle or used in conjunction with fertility medications.
IUI is also commonly suggested when a woman or couple requires donor sperm. Before deciding if IUI is the right approach for you, you will undergo standard infertility testing in consultation with your doctor.
Natural Rate of Conception by Age
The natural likelihood of conception per ovulation cycle varies significantly depending on the woman's age. For couples without fertility issues, women in their early 30s or younger have a natural pregnancy rate of approximately 20 to 25 percent per cycle. However, this rate declines considerably as women move through their mid-to-late 30s. By the early 40s, the chance of pregnancy drops to around 5 percent per cycle. This age-related decline is primarily due to the diminishing quality of eggs within the ovaries.
Intrauterine Insemination (IUI) Pregnancy Rates by Diagnosis
Beyond age, the success of IUI also depends on the couple's specific diagnosis. IUI tends to be most successful in cases where the primary infertility issue is ovulatory, such as with polycystic ovary syndrome (PCOS). In these situations, the treatment most closely replicates the natural per-cycle pregnancy rate.
IUI is also fairly effective in treating mild male factor infertility or unexplained infertility, though the success rates are slightly lower compared to cases where ovulatory dysfunction is the sole issue.
However, IUI is less successful when infertility is caused by decreased egg quality, diseased Fallopian tubes, or endometriosis. IUI cannot improve egg quality or repair damaged anatomical structures. In these cases, as well as with advanced maternal age, it may be advisable to consider transitioning to IVF earlier in the treatment process.
Fertilization typically occurs in the Fallopian tubes before the embryo moves to the uterine cavity for implantation. If the Fallopian tubes are damaged, fertilization may not happen. Even if one Fallopian tube is open while the other is blocked, underlying disease may affect both tubes, preventing them from providing the nurturing environment necessary for fertilization and early embryo development.
Intrauterine Insemination (IUI) Pregnancy Rates by Age
For most couples facing challenges in achieving pregnancy, the chances are not zero but lower than the average conception rate, unless there are severe factors like completely blocked Fallopian tubes, no sperm, or the woman never ovulates. Ovulation induction (or superovulation) combined with IUI can help patients achieve pregnancy rates closer to the natural per-cycle chance of pregnancy for women in their age group who do not experience infertility.
Since the likelihood of pregnancy per IUI treatment cycle is relatively modest, it may require multiple cycles to achieve a successful pregnancy. However, if pregnancy has not occurred after three to four IUI cycles, it might be advisable to consider more advanced treatments, such as in vitro fertilization (IVF).
For women over the age of 40, the chances of pregnancy with IUI are lower, so it is generally recommended to move to IVF sooner, with fewer IUI cycles attempted. After 40, it is advisable for patients to consider IVF earlier in their treatment journey.
Intrauterine insemination (IUI) is a straightforward, low-tech fertility treatment often used as the first step for individuals and couples struggling to conceive naturally.
IUI and other low-tech fertility treatments focus on stimulating the development of one to four eggs, with fertilization occurring naturally within the patient’s body, rather than in a laboratory setting.