Introduction of semen into a female's vagina or cervix by means other than sexual intercourse. First developed for animal breeding in the early 20th century in Russia, it is now also used to induce pregnancy in women whose partners cannot impregnate them. The partner's (or other donor's) semen is inserted with a syringe. Though reasonably successful, artificial insemination in humans raises moral issues that are not yet fully resolved. In livestock, deep-frozen semen from a male animal can be stored for long periods without losing its fertility, thus allowing a single bull to sire as many as 10,000 calves a year.
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Specifically, in artificial insemination, freshly ejaculated sperm, or sperm which has been frozen and thawed, is placed in the cervix (intracervical insemination) (ICI)) or in the female's uterus (intrauterine insemination) (IUI) by artificial means.
Modern techniques for human artificial insemination were first developed for the dairy cattle industry to allow many cows to be impregnated with the sperm of a bull with traits for improved milk production.
The man providing the sperm is usually advised not to ejaculate for two to three days before providing the sample in order to increase the sperm count.
A woman's menstrual cycle is closely observed, by tracking basal body temperature (BBT) and changes in vaginal mucous, or using ovulation kits, ultrasounds or blood tests.
When using intrauterine insemination (IUI), the sperm must immediately be “washed” in a laboratory and concentrated in Hams F10 media without L-glutamine, warmed to 37C. (Adams, Robert, M.D."invitro fertilization technique", Monterey, CA, 1988). The process of “washing” the sperm increases the chances of fertilization and removes any mucus and non-motile sperm in the semen.Pre and post concentration of motile sperm is counted.
If sperm is provided by a sperm donor through a sperm bank, it will be frozen and quarantined for a particular period and the donor will be tested before and after production of the sample to ensure that he does not carry a transmissible disease. Sperm samples donated in this way are produced through masturbation by the sperm donor at the sperm bank. A chemical known as a cryoprotectant is added to the sperm to aid the freezing and thawing process. Further chemicals may be added which separate the most active sperm in the sample as well as extending or diluting the sample so that vials for a number of inseminations are produced.
Earlier, a popular form of artificial insemination was AIC, in which the sperm of the husband and a donor were mixed. The advantage of this stated that the husband was not the biological father of the child. This was important in an age where artificial insemination was considered to be immoral and tantamount to adultery, with the resulting child being considered as illegitimate and having no inheritance rights. The popularity of AIC has reduced to almost nil for a number of reasons, including advances in genetic testing which make it fairly easy to identify the genetic father with a blood test, the advance of medical treatments for male infertility (such as ICSI), and the declining stigma of assisted reproductive technologies in general.
IUI can furthermore be combined with intratubal insemination (ITI), into the Fallopian tube although this procedure is no longer generally regarded as having any beneficial effect compared with IUI ITI however, should not be confused with gamete intrafallopian transfer, where both eggs and sperm are mixed outside the woman's body and then immediately inserted into the Fallopian tube where fertilization takes place. See also in vitro fertilisation (IVF) techniques which may involve the use of partner or donor sperm.
Generally, it is 10 to 15% per cycle using ICI, and and 15-20% per cycle for IUI.
Artificial insemination is used in animals to propagate desirable characteristics of one male to many females or overcome breeding problems, particularly in the cases of horses, cattle, pigs, pedigree dogs, and honeybees. Semen is collected, extended, then cooled or frozen. It can be used on site or shipped to the female's location. The small plastic tube holding the frozen semen is referred to as a "straw". To allow the sperm to remain viable during the time before and after it is frozen, the semen is mixed with a solution containing glycerol or other cryoprotectants. An "extender" is a solution that allows the semen from a donor to impregnate more females by making insemination possible with fewer sperm. Antibiotics, such as streptomycin, are sometimes added to the sperm to control some venereal diseases.
Artificial insemination of farm animals is very common in today's agriculture industry in the developed world, especially for breeding dairy cattle (75% of all inseminations) and swine (up to 85% of all inseminations). It provides an economical means for a livestock grower to breed their herds with males having very desirable traits.
Although common with cattle and swine, AI is seldom practised in the breeding of horses. Most equine associations and race tracks in North America only accept horses that have been conceived under "natural cover", or actual physical mating between a mare and a stallion. All Thoroughbred bloodstock (race horses), are conceived naturally, no AI is allowed in Thoroughbred breeding.