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What is intrauterine insemination (IUI)?

IUI bypasses the cervix and places the sperm directly at the top of the uterus. From there, sperm can reach the egg in the fallopian tubes within seconds.


Why it’s done

IUI is often effective in treating mild male factor infertility, since sperm are washed and concentrated prior to placing them in the uterus. IUI is also effective in treating cervical factor infertility because the sperm are inserted through the cervix using a catheter, thus bypassing poor mucus and/or antibodies against sperm.


Types of IUI

Natural cycle insemination

When a woman does not take any fertility medications in her IUI cycle, we refer to it as natural cycle insemination. Ovulation is timed by the patient, using ovulation predictor kits that test the urine. We can assist the timing using ultrasound examinations or blood work, if needed. The couple arrives at our office on the day of the insemination and her partner provides the sperm. If preferable, sperm can be collected at home in a special sterile container. Sperm washing is done at our lab, which prepares a concentrated specimen to be injected into the uterus using a small catheter during a painless procedure. Note that unprepared sperm should never be placed directly into the uterus, as severe adverse reactions may result.

Medication assisted insemination

The IUI procedure is largely the same when women use either Clomid or Letrozole, or rarely injectable fertility medications (FSH). In these treatment cycles, however, women are monitored more closely and the timing of ovulation may be controlled with medications. This type of IUI carries a higher risk of multiple births since more than one egg is often produced; there is a potential for high order (greater than two) multiple births. In order to manage the risk of multiple births, these IUI cycles must be monitored closely by a fertility specialist to help optimally reduce the risk. Dosage adjustments based upon each patient’s individual response may be required.

Donor sperm IUI

Donor sperm, in combination with intrauterine insemination (IUI), is a common treatment in the following cases:

  • Absence of sperm in the male partner or severe sperm abnormalities (male infertility)
  • A female patient does not have a male partner
  • To help same-sex couples start their families
  • There are genetic abnormalities in the male 

Note that donor sperm was once the only treatment option for moderate to severe male factor infertility. With the advent of ICSI, combined with in vitro fertilization (IVF), a pregnancy can be created even when there are no sperm in the ejaculate. Oftentimes the sperm can be harvested directly from the reproductive tract and inserted directly into the egg. This makes it possible for male factor infertility patients to have genetically related children.

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