Artificial insemination was developed to treat certain types of infertility. It involves manually introducing sperm into the reproductive tract of a woman in order to help her get pregnant. It’s particularly useful if a man is unable to ejaculate during sexual intercourse or has sperm with low motility which might be unable to reach the egg after intercourse. It has also been used for women with thick cervical mucus which hinders the passage of sperm. It is the method of choice for inseminating a surrogate mother if she is relying on using her own fertilized eggs rather than having an embryo implanted in her uterus.

The sperm can be either fresh or frozen-thawed. The latter is strongly recommended because the processes involved in freezing minimize the chance that infectious microorganisms will be present.

The procedure must be timed to coincide with ovulation, whether this occurs naturally or is stimulated by hormone treatment. The most accurate way to determine the onset of ovulation is to monitor hormone levels in blood or urine; this gives better results than monitoring body temperature or vaginal discharge.

There are several methods of insemination; the success rate for most of them is around 15 to 30%.

1. Intrauterine insemination (IUI). IUI involves introducing sperm directly into the uterus via a catheter. This is an invasive method but has a higher success rate. Washed sperm must be used to avoid uterine cramping due to prostaglandins in unprocessed semen. IUI tends to be more successful if used in combination with fertility drugs, although several cycles are often needed before the woman gets pregnant.

2. Intracervical insemination (ICI). ICI is less expensive and invasive than IUI and also has good success rates. Because the sperm are deposited in the cervix rather than the uterus, they must be motile, so his method is unsuitable for infertility due to low-motility sperm. Sperm washing increases the chance of a successful outcome.

3. Intravaginal insemination (IVI). IVI is the simplest insemination technique and involves introducing sperm into the vagina, as is done during normal intercourse. It is not normally necessary to use washed sperm unless there is a known risk of infection from the semen. Since the sperm have to swim to the uterus, they must be motile.

4. Intratubal insemination (ITI). ITI is an uncommon and highly invasive (and expensive) method. Since sperm are deposited directly in the fallopian tubes, close to where the eggs are located, the success rate tends to be higher than for the other techniques. This technique can be performed if IUI is unsuccessful.

5. Intrafollicular insemination (IFI). IFI involves introducing sperm directly into the ovarian follicles where the eggs are developing. This is a very invasive procedure and does not have an especially high success rate. It appears to have no advantages over IFI.

After the insemination procedure, the woman should remain lying down for a few minutes; she can then resume normal activity. If the procedure does not result in pregnancy, it can be repeated. If pregnancy does not result after six treatments, further medical consultation is advisable.