In vivo fertilization

Insemination is the deliberate introduction of sperm into a female animal or plant 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 (egg-laying) animal.

In mammals, insemination normally occurs during sexual intercourse, but insemination can take place in other ways, such as artificial insemination. Each form of insemination has legal, moral and interpersonal implications. Whether insemination takes place naturally or by artificial means, however, the pregnancy and the progress of it will be the same.

Insemination may be called in vivo fertilisation (from in vivo meaning "within the living") because an egg is fertilized inside the body, and is thus essentially the opposite of in vitro fertilisation.

In plants, the process of insemination is referred to as pollination.

Insemination of a woman by sexual intercourse is technically referred to as "natural insemination" (NI) i.e. insemination by natural means. In humans, a woman may be inseminated or impregnated by sexual intercourse with a male who may or not be the woman's normal sexual partner.

The incidence of natural insemination by sperm is usually a private matter, and may also carry greater 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 is liable for child support and custody rights of the child.

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Wikipedia