Insemination is the introduction of sperm into a female animal’s reproductive system for the purpose of impregnating or fertilizing the female for sexual reproduction. The sperm is introduced into the uterus of a mammal or the oviduct of an oviparous animal. In mammals, insemination normally occurs during sexual intercourse or copulation, but insemination can take place in other ways, such as by artificial insemination. In humans, the act and form of insemination has legal, moral and interpersonal implications. However, whether insemination takes place naturally or by artificial means, the pregnancy and the progress of it will be the same. Insemination may be called in vivo fertilisation because an egg is fertilized inside the body, this is in contrast with in vitro fertilisation. In plants, the fertilization process is referred to as pollination. It is the process of transfer of pollen grains from one anther to stigma of other plants.
Natural insemination
Insemination of a woman by sexual intercourse is referred to as "natural insemination" . Natural insemination involves ejaculation during penile–vaginal penetration, with the erect penis deep inside the vagina, which is well lubricated. If an artificial lubricant needs to be used, care must be taken that it does not have spermicidal properties. During ejaculation, semen, containing male gametes known as sperm, is expelled through the penis into the moist and warm environment of the female’s reproductive tract. The semen then passes from the vagina through the vaginal vault, cervix and into the uterus, and then into the fallopian tubes. The average volume of semen produced at ejaculation is 2 to 5ml. Of the millions of sperm propelled during ejaculation, if an egg or ovum is present in a fallopian tube, fertilization may be achieved when any sperm reaches the ovum, at which point the objective of insemination is achieved. In most cultures, insemination by a male through sexual intercourse, whether the woman's husband, normal sex partner or not, is subject to social and sexual inhibitions and taboos, and has legal, moral and interpersonal implications. The term is also used in the context of third-party insemination, where a male who is not the woman's usual sexual partner fathers a child for the woman by providing his sperm through sexual intercourse rather than by providing his sperm for it to be used to produce a pregnancy in the woman by artificial means. The incidence of natural insemination by a sperm donor is usually a private matter, and may also carry greater health risks than where sperm has been processed by a fertility center. Advocates claim natural insemination generates higher pregnancy rates and a more 'natural' conception which does not involve the intervention and intrusion of third parties. However, it has not been medically proven that natural insemination has an increased chance of pregnancy. Additionally, conceiving through natural insemination is considered a natural process, so the father may be liable for child support and have custody and other rights of the child. The law usually draws a distinction between a man fathering a child by natural means, and a man who provides his sperm for it to be used to father a child by artificial means.
Artificial insemination is the introduction of sperm into the reproductive tract of a female by means other than sexual intercourse for the purpose of impregnating or fertilizing the female. In humans, artificial insemination may be used when a woman or her normal sex partner cannot, for any of a number of reasons, conceive by natural means. A number of artificial insemination strategies are available, including intracervical insemination and intrauterine insemination. Compared with natural insemination, artificial insemination may be more invasive, and may require professional assistance and medical expertise, which will have a higher cost. ICI attempts to simulate natural insemination, without the sexual element. It is painless and is the simplest, easiest and most common method of artificial insemination, and can be performed in the home, either by the female on herself or with non-professional assistance. ICI involves the introduction of unwashed or raw semen into the vagina at the entrance to the cervix, usually by means of a needleless syringe. The sperm for insemination may be provided by either a sexual partner of the female’s choice or by a sperm donor. Donor sperm is most commonly used by lesbian couples, single women, and heterosexual couples when the male partner is suffering from male infertility. There have been situations where a female has been inseminated with sperm collected from a female’s partner before him going off to war or even harvested after he has already died. There are laws in some countries which restrict and regulate who can donate sperm and who is able to receive artificial insemination, and the consequences of such insemination. Subject to any regulations restricting who can obtain donor sperm, donor sperm is available to all women who, for whatever reason, want or need it. Some women living in a jurisdiction which does not permit artificial insemination in the circumstance in which she finds herself may travel to another jurisdiction which permits it. Artificial insemination has been and continues to be commonly used in livestock breeding as an efficient way of increasing production.
Other forms of insemination
In various other animal species, sperm can be introduced into the female's reproductive tract by various means. For example, in some species of hemiptera sperm can be introduced violently by traumatic insemination, injection through the body wall. In some species of animals, sperm finds its way through the body wall when the spermatophore is left in contact with the female's skin, such as in the onychophora.
