Insemination is the introduction of

sperm Sperm (: sperm or sperms) is the male reproductive Cell (biology), cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm ...

(in

semen Semen, also known as seminal fluid, is a bodily fluid that contains spermatozoon, spermatozoa which is secreted by the male gonads (sexual glands) and other sexual organs of male or hermaphrodite, hermaphroditic animals. In humans and placen ...

) into a female or hermaphrodite's

reproductive system The reproductive system of an organism, also known as the genital system, is the biological system made up of all the anatomical organs involved in sexual reproduction. Many non-living substances such as fluids, hormones, and pheromones are al ...

in order to fertilize the

ovum The egg cell or ovum (: ova) is the female reproductive cell, or gamete, in most anisogamous organisms (organisms that reproduce sexually with a larger, female gamete and a smaller, male one). The term is used when the female gamete is not capa ...

through

sexual reproduction Sexual reproduction is a type of reproduction that involves a complex life cycle in which a gamete ( haploid reproductive cells, such as a sperm or egg cell) with a single set of chromosomes combines with another gamete to produce a zygote tha ...

. The sperm enters into the

uterus The uterus (from Latin ''uterus'', : uteri or uteruses) or womb () is the hollow organ, organ in the reproductive system of most female mammals, including humans, that accommodates the embryonic development, embryonic and prenatal development, f ...

of a

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

or the

oviduct The oviduct in vertebrates is the passageway from an ovary. In human females, this is more usually known as the fallopian tube. The eggs travel along the oviduct. These eggs will either be fertilized by spermatozoa to become a zygote, or will dege ...

of an

oviparous Oviparous animals are animals that reproduce by depositing fertilized zygotes outside the body (i.e., by laying or spawning) in metabolically independent incubation organs known as eggs, which nurture the embryo into moving offsprings kno ...

(egg-laying) animal. Female humans and other mammals are inseminated during

sexual intercourse Sexual intercourse (also coitus or copulation) is a sexual activity typically involving the insertion of the Erection, erect male Human penis, penis inside the female vagina and followed by Pelvic thrust, thrusting motions for sexual pleasure ...

or copulation, but can also be inseminated by

artificial insemination Artificial insemination is the deliberate introduction of sperm into a female's cervix or uterine cavity for the purpose of achieving a pregnancy through in vivo fertilization by means other than sexual intercourse. It is a fertility treatment ...

. 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 (from ''

in vivo Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, an ...

'' meaning "within the living") because an

egg An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the ...

is fertilized inside the body, this is in contrast with

in vitro fertilisation In vitro fertilisation (IVF) is a process of fertilisation in which an ovum, egg is combined with spermatozoon, sperm in vitro ("in glass"). The process involves monitoring and stimulating the Ovulation cycle, ovulatory process, then removing ...

(IVF).

Plants

In plants, the fertilization process is referred to as

pollination Pollination is the transfer of pollen from an anther of a plant to the stigma (botany), stigma of a plant, later enabling fertilisation and the production of seeds. Pollinating agents can be animals such as insects, for example bees, beetles or bu ...

. It is the process of transfer of pollen grains from one

anther The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

to the stigma of other plants.

Natural insemination

Insemination during

through penile–vaginal penetration is referred to as ''natural insemination'' (i.e., insemination by natural means). If an artificial lubricant needs to be used, care must be taken that it does not have spermicidal properties. During

ejaculation Ejaculation is the discharge of semen (the ''ejaculate''; normally containing sperm) from the penis through the urethra. It is the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. ...

, containing male gametes known as

, is expelled from the

penis A penis (; : penises or penes) is a sex organ through which male and hermaphrodite animals expel semen during copulation (zoology), copulation, and through which male placental mammals and marsupials also Urination, urinate. The term ''pen ...

through the male

urethra The urethra (: urethras or urethrae) is the tube that connects the urinary bladder to the urinary meatus, through which Placentalia, placental mammals Urination, urinate and Ejaculation, ejaculate. The external urethral sphincter is a striated ...

into the moist and warm environment of the female reproductive tract. In humans, semen is usually ejaculated into the posterior vaginal fornix in direct contact with

cervical mucus The cervix (: cervices) or cervix uteri is a dynamic fibromuscular sexual organ of the female reproductive system that connects the vagina with the uterine cavity. The human female cervix has been documented anatomically since at least the tim ...

, though sperm may swim from other areas of the vagina or vulva to the

cervix The cervix (: cervices) or cervix uteri is a dynamic fibromuscular sexual organ of the female reproductive system that connects the vagina with the uterine cavity. The human female cervix has been documented anatomically since at least the time ...

. The average volume of semen produced at ejaculation is 2 to 5 millilitres (about a teaspoon), containing an average of 182 million sperm. Only a small proportion of the sperm in each ejaculation reach the site of fertilization in the

fallopian tube The fallopian tubes, also known as uterine tubes, oviducts or salpinges (: salpinx), are paired tubular sex organs in the human female body that stretch from the Ovary, ovaries to the uterus. The fallopian tubes are part of the female reproduct ...

s, their numbers decreasing exponentially as they progress through the female reproductive tract. The majority of sperm either die in the acidic environment of the vagina or drip out with the semen. Prior to

ovulation Ovulation is an important part of the menstrual cycle in female vertebrates where the egg cells are released from the ovaries as part of the ovarian cycle. In female humans ovulation typically occurs near the midpoint in the menstrual cycle and ...

, the cervical mucus becomes thinner and more hospitable to sperm. Sperm swim rapidly into the uterus upon encountering cervical mucus, though many become lost in the cervical crypts where they either die or are delayed. Further attrition occurs in the uterus, where sperm are attacked by the female immune system. Only about 100–1000 sperm reach the fallopian tubes, where they may survive for up to six days. If ovulation occurs and the sperm encounter an

in the fallopian tube, fertilization may occur. A woman may also be naturally inseminated while having penile–vaginal intercourse for pleasure without any intent to conceive. This may be unintentional as a result of the failure of a barrier or

behavioural Behavior (American English) or behaviour (British English) is the range of actions of individuals, organisms, systems or artificial entities in some environment. These systems can include other systems or organisms as well as the inanimate ph ...

method of

contraception Birth control, also known as contraception, anticonception, and fertility control, is the use of methods or devices to prevent pregnancy. Birth control has been used since ancient times, but effective and safe methods of birth control only be ...

, or may be intentional if relying on female contraceptive methods or indifferent to the possibility of pregnancy. 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 (i.e., a sperm donor) 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 (i.e. by artificial insemination).

Artificial insemination

Artificial insemination 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 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 (ICI) and intrauterine insemination (IUI). 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; it 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

, usually by means of a needleless syringe. The sperm for insemination may be provided either by a sexual partner of the female's choice or by a sperm donor. Donor sperm is most commonly used by lesbian couples and single women, and by heterosexual couples when the male partner is suffering from

male infertility Male infertility refers to a sexually mature male's inability to impregnate a fertile female. Male infertility can wholly or partially account for 40% of infertility among couples who are trying to have children. "A problem with the male is the s ...

. In some circumstances, sperm has been collected from males before they go off to war, or even right after they have died, and used to inseminate their female partners. In some countries, there are laws restricting and regulating who can donate sperm, who can receive artificial insemination, and what the legal consequences are of such insemination. Subject to any such restrictions, donor sperm is available to all women who want or need it. Women who live in a jurisdiction that prohibits them from being artificially inseminated may sometimes choose to obtain it by traveling to a jurisdiction that 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 Hemiptera (; ) is an order of insects, commonly called true bugs, comprising more than 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from ...

sperm can be introduced violently by

traumatic insemination Traumatic insemination, also known as hypodermic insemination, is the mating practice in some species of invertebrates in which the male pierces the female's abdomen with his aedeagus and injects his sperm through the wound into her abdominal ca ...

parenteral In pharmacology and toxicology, a route of administration is the way by which a drug, fluid, poison, or other substance is taken into the body. Routes of administration are generally classified by the location at which the substance is applied. ...

injection through the body wall. In some species of animals, sperm finds its way through the body wall when the

spermatophore A spermatophore, from Ancient Greek σπέρμα (''spérma''), meaning "seed", and -φόρος (''-phóros''), meaning "bearing", or sperm ampulla is a capsule or mass containing spermatozoa created by males of various animal species, especiall ...

is left in contact with the female's skin, such as in the

onychophora Onychophora (from , , "claws"; and , , "to carry"), commonly known as velvet worms (for their velvety texture and somewhat wormlike appearance) or more ambiguously as peripatus (after the first described genus, ''Peripatus''), is a phylum of el ...

(velvet worms).

References

External links