Birth

{{Short description|Process of bearing offspring}}
{{hatnote|This article is primarily about birth in non-human mammals and other animals. For birth in humans specifically, see [[Childbirth]]. For other uses, see [[Birth (disambiguation)]].}}
{{Redirect|Parturition|the ''Star Trek'' episode|Parturition (Star Trek: Voyager)}}
[[File:Lambing in England -10March2012 (2).jpg|right|thumb|[[Lambing]]: the mother licks the first lamb while giving birth to the second]]
'''Birth''' is the act or process of bearing or bringing forth [[offspring]],<ref>"birth". [[OED Online]]. June 2013. Oxford University Press. [http://www.oed.com/view/Entry/19395 Entry 19395] {{Webarchive|url=https://web.archive.org/web/20221122112522/https://www.oed.com/view/Entry/19395 |date=2022-11-22 }} (accessed 30 August 2013).</ref> also referred to in technical contexts as '''parturition'''. In mammals, the process is initiated by hormones which cause the muscular walls of the [[uterus]] to contract, expelling the fetus at a developmental stage when it is ready to feed and breathe.

In some species, the offspring is [[precocial]] and can move around almost immediately after birth but in others, it is [[altricial]] and completely dependent on parenting.

In [[marsupial]]s, the fetus is born at a very immature stage after a short [[gestation]] and develops further in its mother's womb  [[Pouch (marsupial)|pouch]].

It is not only mammals that give birth. Some reptiles, amphibians, fish and invertebrates carry their developing young inside them. Some of these are [[Ovoviviparity|ovoviviparous]], with the eggs being hatched inside the mother's body, and others are [[Viviparity|viviparous]], with the [[embryo]] developing inside their body, as in the case of mammals.

==Human childbirth==
{{main|Childbirth}}
{{Further |Adaptation to extrauterine life}}
[[File:Cephalicpre.JPG|right|upright|thumb|An illustration of normal [[Cephalic presentation|head-first presentation]] by the obstetrician [[William Smellie (obstetrician)|William Smellie]] from about 1792. The [[Rupture of membranes|membranes have ruptured]] and the cervix is fully dilated.]]
Humans usually produce a single offspring at a time. The mother's body is prepared for birth by [[hormone]]s produced by the [[pituitary gland]], the [[ovary]] and the [[placenta]].<ref name=Dorit>{{cite book |title=Zoology |last1=Dorit |first1=R. L. |last2=Walker |first2=W. F. |last3=Barnes |first3=R. D. |year=1991 |publisher=Saunders College Publishing |isbn=978-0-03-030504-7 |pages=[https://archive.org/details/zoology0000dori/page/526 526–527] |url=https://archive.org/details/zoology0000dori/page/526 }}</ref> The total [[gestation period]] from [[human fertilization|fertilization]] to birth is normally about 38 weeks (birth usually occurring 40 weeks after the last [[Menstruation|menstrual period]]). The normal process of childbirth takes several hours and has three stages. The first stage starts with a series of involuntary contractions of the muscular walls of the [[uterus]] and gradual dilation of the cervix. The active phase of the first stage starts when the cervix is dilated more than about 4&nbsp;cm in diameter and is when the contractions become stronger and regular. The head (or the buttocks in a [[breech birth]]) of the baby is pushed against the [[cervix]], which gradually dilates until it is fully dilated at 10&nbsp;cm diameter.  At some time, the [[amniotic sac]] bursts and the [[amniotic fluid]] escapes (also known as [[rupture of membranes]] or breaking the water).<ref>NICE (2007). Section 1.6, ''Normal labour: first stage''</ref> In stage two, starting when the cervix is fully dilated, strong contractions of the uterus and active pushing by the mother expels the baby out through the [[Human vagina|vagina]], which during this stage of labour is called a birth canal as this passage contains a baby, and the baby is born with [[umbilical cord]] attached.<ref>NICE (2007). Section 1.7, ''Normal labour: second stage''</ref> In stage three, which begins after the birth of the baby, further contractions expel the [[placenta]], amniotic sac, and the remaining portion of the umbilical cord usually within a few minutes.<ref>NICE (2007). Section 1.8, ''Normal labour: third stage''</ref>

Enormous changes take place in the newborn's circulation to enable [[breathing]] in air. In the uterus, the [[fetus]] is dependent on circulation of blood through the placenta for sustenance including gaseous exchange and the unborn baby's blood bypasses the lungs by flowing through the [[foramen ovale (heart)|foramen ovale]], which is a hole in the septum dividing the [[right atrium]] and [[left atrium]]. After birth the umbilical cord is clamped and cut, the baby starts to breathe air, and blood from the [[right ventricle]] starts to flow to the lungs for gaseous exchange and oxygenated blood returns to the [[left atrium]], which is pumped into the [[left ventricle]], and then pumped into the main arterial system.  As a result of these changes, the blood pressure in the left atrium exceeds the pressure in the right atrium, and this pressure difference forces the foramen ovale to close separating the left and right sides of the heart. The [[umbilical vein]], [[umbilical arteries]], [[ductus venosus]] and [[ductus arteriosus]] are not needed for life in air and in time these vessels become ligaments (embryonic remnants).<ref>{{cite book |title=The Human Body Book |page=215 |year=2007 |isbn=978-1-8561-3007-3 |publisher=[[Dorling Kindersley]] |editor1=Houston, Rob |editor2=Lea, Maxine (art)}}</ref>

==Other mammals==
Large [[mammal]]s, such as [[primate]]s, [[cattle]], [[horse]]s, some [[antelope]]s, [[giraffe]]s, [[hippopotamus]]es, [[rhinoceros]]es, [[elephant]]s, [[Pinniped|seals]], [[whale]]s, [[dolphin]]s, and [[porpoise]]s, generally are [[Pregnancy (mammals)|pregnant]] with one offspring at a time, although they may have twin or multiple births on occasion.

In these large animals, the birth process is similar to that of a human, though in most the offspring is [[precocial]]. This means that it is born in a more advanced state than a human baby and is able to stand, walk and run (or swim in the case of an aquatic mammal) shortly after birth.<ref name=Dorit/>

In the case of whales, dolphins and porpoises, the single calf is normally born tail first which minimizes the risk of drowning.<ref name="Simmonds 2007 p.32">{{cite book | last=Simmonds | first=Mark | title=Whales and Dolphins of the World | publisher=Bloomsbury Wildlife | date=2007 | isbn=978-1-84537-820-2 | oclc=159685085 | ol=9540216M | chapter=1 | page=32}}</ref> The mother encourages the newborn calf to rise to the surface of the water to breathe.<ref>{{cite web |url=http://humpbackwhale.homestead.com/Humpback-Whale-Calf.html |title=Humpback Whale Calves |author=Crockett, Gary |year=2011 |publisher=Humpback whales Australia |access-date=2013-08-28 |archive-url=https://web.archive.org/web/20170227041536/http://humpbackwhale.homestead.com/Humpback-Whale-Calf.html |archive-date=2017-02-27 |url-status=dead }}</ref>

Most smaller mammals have multiple births, producing litters of young which may number twelve or more. In these animals, each fetus is surrounded by its own amniotic sac and has a separate placenta. This separates from the wall of the uterus during labor and the fetus works its way towards the birth canal.{{citation needed|date=April 2014}}

Large mammals which give birth to twins is much more rare, but it does occur occasionally even for mammals as large as elephants. In April 2018,  approximately 8-month old elephant twins were sighted joining their mother's herd in the Tarangire National Park of Tanzania, estimated to have been born in August 2017.<ref>{{Cite news|url=https://www.asiliaafrica.com/trunk-twins-elephant-twins-born-in-tarangire/|title=Trunk Twins : Elephant Twins Born in Tarangire {{!}} Asilia Africa|date=2018-04-06|work=Asilia Africa|access-date=2018-04-06|language=en-GB|archive-date=2018-04-07|archive-url=https://web.archive.org/web/20180407001742/https://www.asiliaafrica.com/trunk-twins-elephant-twins-born-in-tarangire/|url-status=live}}</ref>

===Cattle===
[[File:Cow giving birth, in Laos (step by step).jpg|thumb|alt=Series of photos showing a cow giving birth|A cow giving birth]]
Birthing in [[cattle]] is typical of a larger mammal. A [[cow]] goes through three stages of labor during normal delivery of a calf. During stage one, the animal seeks a quiet place away from the rest of the herd.  Hormone changes cause soft tissues of the birth canal to relax as the mother's body prepares for birth. The contractions of the [[uterus]] are not obvious externally, but the cow may be restless. She may appear agitated, alternating between standing and lying down, with her tail slightly raised and her back arched. The fetus is pushed toward the birth canal by each contraction and the cow's [[cervix]] gradually begins to dilate. Stage one may last several hours, and ends when the cervix is fully dilated. Stage two can be seen to be underway when there is external protrusion of the [[amniotic sac]] through the vulva, closely followed by the appearance of the calf's front hooves and head in a front presentation (or occasionally the calf's tail and rear end in a posterior presentation).<ref name=Alberta/>  During the second stage, the cow will usually lie down on her side to push and the calf progresses through the birth canal. The complete delivery of the calf (or calves in a multiple birth) signifies the end of stage two. The cow scrambles to her feet (if lying down at this stage), turns round and starts vigorously licking the calf. The calf takes its first few breaths and within minutes is struggling to rise to its feet. The third and final stage of labor is the delivery of the [[placenta]], which is usually expelled within a few hours and is often eaten by the normally [[Herbivore|herbivorous]] cow.<ref name=Alberta>{{cite web |url=http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex3451 |title=Calving |date=2000-02-01 |publisher=Alberta: Agriculture and Rural Development |access-date=2013-08-28 |archive-date=2013-09-12 |archive-url=https://web.archive.org/web/20130912011555/http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex3451 |url-status=live }}</ref><ref name=ohio>{{cite web |url=http://ohioline.osu.edu/vme-fact/pdf/0029.pdf |title=Calving Management in Dairy Herds: Timing of Intervention and Stillbirth |year=2012 |publisher=The Ohio State University College of Veterinary Medicine Extension |access-date=2013-12-17 |archive-date=2013-12-19 |archive-url=https://web.archive.org/web/20131219005040/http://ohioline.osu.edu/vme-fact/pdf/0029.pdf |url-status=live }}</ref>

===Dogs===
{{Further|Canine reproduction#Gestation and litters}}
Birth is termed whelping in dogs.<ref name=":0">{{Cite journal|last=Kustritz, M.|year=2005|title=Reproductive behaviour of small animals|url=https://www.scribd.com/document/263302746/Conducta-Reproductiva-en-Pequenos-Animales|journal=Theriogenology|volume=64|issue=3|pages=734–746|doi=10.1016/j.theriogenology.2005.05.022|pmid=15946732|access-date=2016-11-18|archive-date=2016-11-18|archive-url=https://web.archive.org/web/20161118041254/https://www.scribd.com/document/263302746/Conducta-Reproductiva-en-Pequenos-Animales|url-status=live}}</ref> Among [[dog]]s, as whelping approaches, contractions become more frequent. Labour in the bitch can be divided into 3 stages. The first stage is when the cervix dilates, causing discomfort and restlessness in the dog. Common signs of this stage are panting, fasting, and/or vomiting. This may last up to 12 hours.<ref name=":0" /> Stage two is the passage of the offspring.<ref name=":0" /> The [[amniotic sac]] looking like a glistening grey balloon, with a puppy inside, is propelled through the [[vulva]].  After further contractions, the sac is expelled and the bitch breaks the membranes, releasing clear fluid and exposing the puppy. The mother chews at the umbilical cord and licks the puppy vigorously, which stimulates it to breathe. If the puppy has not taken its first breath within about six minutes, it is likely to die. Further puppies follow in a similar way one by one usually with less straining than the first usually at 15-60-minute intervals. If a pup has not been passed in 2 hours a veterinarian should be contacted.<ref name=":0" /> Stage three is the passing of the placentas. This often occurs in conjunction with stage two with the passing of each offspring.<ref name=":0" /> The mother will then usually eat the afterbirth.<ref name=petmd>{{cite web |url=http://www.petmd.com/dog/puppycenter/health/evr_dg_whelping_new_puppies_on_the_way |title=Whelping: New Puppies On The Way! |author=Dunn, T.J. |work=Puppy Center |publisher=Pet MD |access-date=2013-08-28 |archive-date=2018-08-24 |archive-url=https://web.archive.org/web/20180824034316/https://www.petmd.com/dog/puppycenter/health/evr_dg_whelping_new_puppies_on_the_way |url-status=live }}</ref> This is an adaption to keep the den clean and prevent its detection by predators.<ref name=":0" />

===Marsupials===
{{See also|Marsupial#Reproductive system|Marsupial#Early development}}
[[File:Joey in pouch.jpg|thumb|A [[kangaroo]] joey firmly attached to a nipple inside the pouch]]
An infant [[marsupial]] is born in a very immature state.<ref name="Tyndale-BiscoeRenfree1987">{{cite book|author1=Hugh Tyndale-Biscoe|author2=Marilyn Renfree|title=Reproductive Physiology of Marsupials|url=https://books.google.com/books?id=HpjovN0vXW4C&q=birth|date=30 January 1987|publisher=Cambridge University Press|isbn=978-0-521-33792-2}}</ref> The gestation period is usually shorter than the intervals between oestrus periods. The first sign that a birth is imminent is the mother cleaning out her [[Pouch (marsupial)|pouch]]. When it is born, the infant is pink, blind, furless and a few centimetres long. It has nostrils in order to breathe and forelegs to cling onto its mother's hairs but its hind legs are undeveloped. It crawls through its mother's fur and makes its way into the pouch. Here it fixes onto a teat which swells inside its mouth. It stays attached to the teat for several months until it is sufficiently developed to emerge.<ref>{{cite web |url=http://www.naturalworlds.org/thylacine/biology/reproduction/reproduction_5.htm |title=Reproduction and development |publisher=Thylacine Museum |access-date=2013-08-28 |archive-date=2017-06-21 |archive-url=https://web.archive.org/web/20170621040826/http://www.naturalworlds.org/thylacine/biology/reproduction/reproduction_5.htm |url-status=live }}</ref> Joeys are born with "oral shields"; in species without pouches or with rudimentary pouches these are more developed than in forms with well-developed pouches, implying a role in maintaining the young attached to the mother's nipple.<ref>{{cite journal | author = Yvette Schneider Nanette | date = Aug 2011 | title = The development of the olfactory organs in newly hatched monotremes and neonate marsupials | journal = J. Anat. | volume = 219 | issue = 2| pages = 229–242 | doi = 10.1111/j.1469-7580.2011.01393.x | pmc = 3162242 | pmid=21592102}}</ref>

==Other animals==
[[File:Rodząca dafnia.jpg|thumb|A [[Cladocera]] giving birth (100x magnification)]]
Many reptiles and the vast majority of invertebrates, most fish, amphibians and all birds are [[Oviparity|oviparous]], that is, they lay eggs with little or no embryonic development taking place within the mother. In aquatic organisms, fertilization is nearly always external with sperm and eggs being liberated into the water (an exception is sharks and rays, which have internal fertilization<ref>Sea World, [http://www.seaworld.org/animal-info/info-books/sharks-&-rays/reproduction.htm Sharks & Rays] {{Webarchive|url=https://web.archive.org/web/20131110032029/http://www.seaworld.org/animal-info/info-books/sharks-%26-rays/reproduction.htm |date=2013-11-10 }}; accessed 2013.09.09.</ref>). Millions of eggs may be produced with no further parental involvement, in the expectation that a small number may survive to become mature individuals. Terrestrial invertebrates may also produce large numbers of eggs, a few of which may avoid predation and carry on the species. Some fish, reptiles, and amphibians have adopted a different strategy and invest their effort in producing a small number of young at a more advanced stage which are more likely to survive to adulthood. Birds care for their young in the nest and provide for their needs after hatching and it is perhaps unsurprising that internal development does not occur in birds, given their need to fly.<ref name=Attenborough>{{cite book |title=The Trials of Life |last=Attenborough |first=David |year=1990 |isbn=9780002199124 |pages=26–30 |publisher=Collins }}</ref>

[[Ovoviviparity]] is a mode of reproduction in which [[embryo]]s develop inside [[egg (biology)|egg]]s that remain in the mother's body until they are ready to hatch. Ovoviviparous animals are similar to [[viviparous]] species in that there is [[internal fertilization]] and the young are born in an advanced state, but differ in that there is no [[placenta]]l connection and the unborn young are nourished by [[egg yolk]]. The mother's body provides [[gas exchange]] (respiration), but that is largely necessary for oviparous animals as well.<ref name=Attenborough/> In many [[shark]]s the eggs hatch in the oviduct within the mother's body and the embryos are nourished by the egg's yolk and fluids secreted by glands in the walls of the oviduct.<ref>{{cite journal|last1=Adams|first1=Kye R.|last2=Fetterplace|first2=Lachlan C.|last3=Davis|first3=Andrew R.|last4=Taylor|first4=Matthew D.|last5=Knott|first5=Nathan A.|title=Sharks, rays and abortion: The prevalence of capture-induced parturition in elasmobranchs|journal=Biological Conservation|date=January 2018|volume=217|pages=11–27|doi=10.1016/j.biocon.2017.10.010|s2cid=90834034 |url=http://marxiv.org/k2qvy/|access-date=2019-06-30|archive-date=2019-02-23|archive-url=https://web.archive.org/web/20190223020619/https://marxiv.org/k2qvy/|url-status=dead}}</ref> The [[Lamniforme]] sharks practice ''[[oophagy]]'', where the first embryos to hatch consume the remaining eggs and [[sand tiger shark]] pups [[cannibal]]istically consume neighbouring embryos. The [[requiem sharks]] maintain a ''placental'' link to the developing young, this practice is known as [[viviparity]]. This is more analogous to mammalian gestation than to that of other fishes. In all these cases, the young are born alive and fully functional.<ref>{{cite web |url=http://www.seaworld.org/animal-info/info-books/sharks-&-rays/birth-&-care.htm |title=Birth and care of young |work=Animals: Sharks and rays |publisher=Busch Entertainment Corporation |access-date=2013-08-28 |url-status=dead |archive-url=https://web.archive.org/web/20130803103514/http://www.seaworld.org/animal-info/info-books/sharks-%26-rays/birth-%26-care.htm |archive-date=August 3, 2013 }}</ref> The majority of  [[caecilian]]s are ovoviviparous and give birth to already developed offspring. When the young have finished their yolk sacs they feed on nutrients secreted by cells lining the [[oviduct]] and even the cells themselves which they eat with specialist scraping teeth.<ref>{{cite book |title=A Natural History of Amphibians |last1=Stebbins |first1=Robert C. |last2=Cohen |first2=Nathan W. |year=1995 |publisher=Princeton University Press |isbn=978-0-691-03281-8 |pages=172–173 }}</ref> The [[Alpine salamander]] (''Salamandra atra'') and several species of Tanzanian toad in the genus ''[[Nectophrynoides]]'' are ovoviviparous, developing through the larval stage inside the mother's oviduct and eventually emerging as fully formed juveniles.<ref>{{cite book |title=A Natural History of Amphibians |last1=Stebbins |first1=Robert C. |last2=Cohen |first2=Nathan W. |year=1995 |publisher=Princeton University Press |isbn=978-0-691-03281-8 |page=204 }}</ref>

A more developed form of [[viviparity]] called [[placenta|placental viviparity]] is adopted by  some species of [[scorpion]]s<ref>Capinera, John L., ''Encyclopedia of entomology''. Springer Reference, 2008, p. 3311.</ref> and cockroaches,<ref>Costa, James T., ''The Other Insect Societies''. Belknap Press, 2006, p. 151.</ref> certain genera of [[sharks]], [[snake]]s and [[velvet worm]]s. In these, the developing embryo is nourished by some form of placental structure. The earliest known placenta was found recently in a group of extinct fishes called [[Placodermi|placoderms]]. A fossil from [[Australia|Australia's]] [[Gogo Formation]], laid down in the [[Devonian]] period, 380&nbsp;million years ago, was found with an embryo inside it connected by an [[umbilical cord]] to a [[yolk sac]]. The find confirmed the hypothesis that a sub-group of placoderms, called [[ptyctodontida|ptyctodontids]], fertilized their eggs internally. Some fishes that fertilize their eggs internally also give birth to live young, as seen here. This discovery moved our knowledge of live birth back 200&nbsp;million years.<ref name=dennis2008>{{cite journal |title= Nature News: The oldest pregnant mum: Devonian fossilized fish contains an embryo |first= Carina |last= Dennis |date= 2008-05-28 |journal= Nature |doi= 10.1038/453575a |volume= 453 |issue= 7195 |page= 575 |pmid= 18509405 |bibcode= 2008Natur.453..575D |doi-access= free }}</ref> The fossil of another genus was found with three embryos in the same position.<ref name=long2008 >{{cite journal |title= Live birth in the Devonian period |first1= John A. |last1= Long |first2= Kate |last2= Trinastic |first3= Gavin C. |last3= Young |first4= Tim |last4= Senden |date= 2008-05-28 |journal= Nature |doi= 10.1038/nature06966 |volume= 453 |issue= 7195 |pages= 650–652 |pmid=18509443|bibcode= 2008Natur.453..650L |s2cid= 205213348 }}</ref> Placoderms are a sister group of the ancestor of all living jawed fishes ([[Gnathostomata]]), including both [[Chondrichthyes|chondrichthyans]], the sharks & rays, and [[Osteichthyes]], the bony fishes.

Among lizards, the [[viviparous lizard]] ''Zootoca vivipara'', the [[Jackson's chameleon]],<ref>{{Cite web |last=Kundinger |first=Heather |title=Chamaeleo jacksonii (Jacksons chameleon) |url=https://animaldiversity.org/accounts/Chamaeleo_jacksonii/ |access-date=2023-02-27 |website=Animal Diversity Web |language=en |archive-date=2023-02-05 |archive-url=https://web.archive.org/web/20230205212943/https://animaldiversity.org/accounts/Chamaeleo_jacksonii/ |url-status=live }}</ref> [[Anguis|slow worms]] and many species of [[skink]] are viviparous, giving birth to live young. Some are ovoviviparous but others such as members of the genera ''[[Tiliqua]]'' and ''[[Corucia]]'', give birth to live young that develop internally, deriving their nourishment from a mammal-like placenta attached to the inside of the mother's uterus. In a recently described example, an African species, ''Trachylepis ivensi'', has developed a purely reptilian [[placenta]] directly comparable in structure and function to a mammalian placenta.<ref>{{cite journal |vauthors=Blackburn DG, Flemming AF |title=Invasive implantation and intimate placental associations in a placentotrophic African lizard, Trachylepis ivensi (scincidae) |journal=J. Morphol. |volume=273 |issue=2 |pages=137–59 |year=2012 |pmid=21956253 |doi=10.1002/jmor.11011 |s2cid=5191828 }}</ref> Vivipary is rare in [[snake]]s, but [[Boidae|boas]] and [[Viperidae|viper]]s are viviparous, giving birth to live young.<ref>{{cite journal |last1=Neill |first1=Wilfred T. |title=Viviparity in Snakes: Some Ecological and Zoogeographical Considerations |journal=The American Naturalist |date=January 1964 |volume=98 |issue=898 |pages=35–55 |doi=10.1086/282299|s2cid=85209921 }}</ref>

[[File:Aphid-giving-birth.jpg|thumb|Female [[aphid]] giving birth]]
The majority of insects lay eggs but a very few give birth to offspring that are miniature versions of the adult.<ref name=Attenborough/> The [[aphid]] has a complex life cycle and during the summer months is able to multiply with great rapidity. Its reproduction is typically [[parthenogenetic]] and viviparous and females produce unfertilized eggs which they retain within their bodies.<ref>{{Cite journal| doi = 10.1111/j.1095-8312.1979.tb00038.x| issn = 1095-8312| volume = 11| issue = 3| pages = 259–277| last = Blackman| first = Roger L| title = Stability and variation in aphid clonal lineages| journal = Biological Journal of the Linnean Society | year = 1979 }}</ref> The embryos develop within their mothers' [[ovarioles]] and the offspring are [[Cloning|clones]] of their mothers. Female [[Nymph (biology)|nymphs]] are born which grow rapidly and soon produce more female offspring themselves.<ref>{{cite web |url=http://www.backyardnature.net/aphid_lc.htm |title=The aphid life cycle |author=Conrad, Jim |date=2011-12-10 |publisher=The Backyard Nature Website |access-date=2013-08-31 |archive-date=2019-03-18 |archive-url=https://web.archive.org/web/20190318150003/http://www.backyardnature.net/aphid_lc.htm |url-status=live }}</ref>  In some instances, the newborn nymphs already have developing embryos inside them.<ref name=Attenborough/>

==See also==
{{Wikiquote}}
{{div col|colwidth=16em}}
* [[Animal sexual behaviour]]
* [[Breeding season]]
* [[Caesarean section]]
* [[Dystocia]]
* [[Episiotomy]]
* [[Foaling#Foaling|Foaling (horses)]]
* [[Forceps delivery]]
* [[Kegel exercises]]
* [[Mating system]]
* [[Odon device]]
* [[Perineal massage]]
* [[Reproduction]]
* [[Reproductive system]]
* [[Ventouse]]
* [[Birth spacing]]
{{div col end}}

==References==
{{Reflist}}

==Cited texts==
*{{cite web |url=http://publications.nice.org.uk/intrapartum-care-cg55/guidance |publisher=[[NICE]] |title=Intrapartum care: Care of healthy women and their babies during childbirth |date=September 2007 |url-status=dead |archive-url=https://web.archive.org/web/20140426234127/http://publications.nice.org.uk/intrapartum-care-cg55/guidance |archive-date=2014-04-26 }}

{{Authority control}}

[[Category:Birth| ]]
[[Category:Animal developmental biology]]