Editing Labia majora

{{short description|Folds of skin that contain and protect the vulva's other parts}}
{{Infobox anatomy
| Name        = Labia majora
| Latin       = labium majus pudendi
| Image       = 
| Caption     = 
| Width       = 
| Image2      = Labium.JPG
| Caption2   = Labia majora of a human
| Precursor   = [[Labioscrotal swelling]]s
| System      = 
| Part_of    = [[Vulva]]
| Artery      = [[Deep external pudendal artery]], [[superficial external pudendal artery]], [[posterior labial arteries]]
| Vein        = [[Posterior labial veins]], [[internal pudendal veins]]
| Nerve       = [[Perineal branches of posterior femoral cutaneous nerve]], [[genital branch of genitofemoral nerve]], [[posterior labial nerves]], [[anterior labial nerves]], [[pudendal nerve]], [[perineal nerve]]
| Lymph       = 
}}

In [[primate]]s, and specifically in humans, the '''labia majora''' ({{singular}}: '''labium majus'''), also known as the '''outer lips''' or '''outer labia''', are two prominent [[Anatomical terms of location|longitudinal]] [[skin]] folds that extend downward and backward from the [[mons pubis]] to the [[perineum]].<ref>{{cite book|last=Blüm|first=Volker|publisher=Springer Berlin Heidelberg|year = 2012|title=Vertebrate Reproduction: A Textbook|page=74|access-date=November 19, 2023|isbn=978-3-64271-074-2|url=https://books.google.com/books?id=JZfzCAAAQBAJ&pg=PA74}}</ref> Together with the [[labia minora]], they form the [[labia]] of the [[vulva]].

The labia majora are [[Homology (biology)|homologous]] to the male [[scrotum]].<ref>{{Cite web|title=Sex Organ Homologies|url=http://www.meddean.luc.edu/lumen/MedEd/GrossAnatomy/pelvis/homology.html|access-date=2020-08-09|website=www.meddean.luc.edu}}</ref>

==Etymology==
''Labia majora'' is the [[Latin]] plural for big ("major") lips. The Latin term ''labium/labia'' is used in anatomy for a number of usually paired parallel structures, but in English, it is mostly applied to two pairs of parts of the [[vulva]]—labia majora and [[labia minora]]. Traditionally, to avoid confusion with other lip-like structures of the body, the vulvar labia were termed by anatomists in Latin as ''labia majora (''or ''minora) pudendi.''

==Embryology==
Embryologically, they develop from [[labioscrotal folds]].<ref>Manual of Obstetrics. (3rd ed.). Elsevier. pp. 1-16. {{ISBN|9788131225561}}.</ref>

The labia majora after puberty may become of a darker color than the skin outside them and grow [[pubic hair]] on their external surface.

==Function and structure==
The main function of the labia majora is to cover and protect the other parts of the vulva.<ref>{{cite book|last=Kinsey|first=Brian|title=Human Body From A to Z|publisher =Marshall Cavendish Reference|year = 2011|page=465|access-date = September 29, 2023 |isbn= 978-0-76149-976-3 |url=https://books.google.com/books?id=jhlfEAAAQBAJ}}</ref> The labia majora contain the [[labia minora]], [[Labia#Structure|interlabial sulci]], [[clitoral hood]], [[Clitoris#Glans|clitoral glans]], [[Clitoris#Frenulum|frenulum clitoridis]], the [[Hart's Line]], and the [[vulval vestibule]], where the external openings of the [[urethra]] and the [[vagina]] are located. Each labium majus has two surfaces, an outer, pigmented and covered with strong, [[pubic hair]]; and an inner, smooth and beset with large [[sebaceous]] follicles. The labia majora are covered with [[Squamous epithelial cell|squamous epithelium]]. Between the two, there is a considerable quantity of [[areolar]] tissue and [[Adipose tissue|fat]], besides vessels, [[nerves]], and [[glands]]. Below the skin of the labia majora, there is a tissue called the ''dartos muliebris'', which gives them a wrinkled appearance.<ref>{{cite book|last=Fahmy|first=Mohamed A. Baky|title=Normal and Abnormal Scrotum|publisher =Springer International Publishing|year = 2021|page=69|access-date = December 29, 2023 |isbn= 978-3-03083-305-3 |url=https://books.google.com/books?id=hElSEAAAQBAJ&pg=PA69}}</ref>

===Pudendal cleft===
[[File:Vulva - front view.png|thumb|Front view of the vulva. Pudendal cleft at 3.]]

The labia majora constitute the lateral boundaries of the '''pudendal cleft'''. The pudendal cleft, also known as the '''vulvar cleft''' or '''cleft of Venus''' ('''''rima vulvae''''' or '''''rima pudendi''''' in Latin),<ref>{{cite book|last=Gould| first=George M.|title=Gould's Pocket Pronouncing Medical Dictionary|editor=Brownslow, C. V|publisher=P. Blakinston's Son & C., Inc. |year=1936|edition=10}}</ref> is a vertical fissure between the labia majora starting at the basal point of the [[mons pubis]]. After puberty, the clitoral hood and the labia minora can protrude into the pudendal cleft to a variable degree.<ref>{{cite journal |last1=Hennekam |first1=RC |last2=Allanson |first2=JE |last3=Biesecker |first3=LG |last4=Carey |first4=JC |last5=Opitz |first5=JM |last6=Vilain |first6=E |title=Elements of morphology: standard terminology for the external genitalia. |journal=American Journal of Medical Genetics. Part A |date=June 2013 |volume=161A |issue=6 |pages=1238–63 |doi=10.1002/ajmg.a.35934 |pmid=23650202|pmc=4440541 }}</ref>

===Commissures===
[[File:Labia commissures.jpg|thumb|200px|right|A) anterior commissure, B) [[Frenulum of labia minora|fourchette]], C) posterior commissure]]

The labia majora are thicker in front, and form the '''anterior labial commissure''' where they meet below the [[mons pubis]]. Posteriorly, they are not really joined, but appear to become lost in the neighboring integument, ending close to, and nearly parallel to, each other. Together with the connecting skin between them, they form another [[commissure]], the '''posterior labial commissure''', which is also the posterior boundary of the vulva. The interval between the posterior commissure and the [[Human anus|anus]], from 2.5 to 3&nbsp;cm in length, constitutes the [[perineum]].<ref>{{Gray's|page=1265|inline=1}}</ref> The anterior region of the perineum is known as the [[urogenital triangle]], which separates it from the anal region. Between the labia majora and the inner [[thigh]]s are the '''labiocrural folds'''. Between the labia majora and labia minora are the interlabial sulci. Labia majora [[atrophy]] after [[menopause]].

==In non-human primates==
While the labia majora is present in all female primates, many have them until adulthood or become inconspicuous around that period.<ref>{{cite book|last=Sheets-Johnstone|first=Maxine|publisher=Temple University Press|year = 2010|title=The Roots of Thinking|page=184|access-date=November 19, 2023|isbn=978-1-43990-365-0|url=https://books.google.com/books?id=2X0EXP5ahtsC&pg=PA184}}</ref> Primates besides humans that always have visible labia majora are [[bonobo]]s, [[Strepsirrhini|strepsirrhines]], [[tarsier]]s, [[Cebidae|cebid monkeys]], and [[gibbon]]s.<ref>{{cite book|last=Ankel-Simons|first=Friderun|publisher=Elsevier Science|year = 2012|title=Primate Anatomy: An Introduction|page=523|access-date=November 19, 2023|isbn=978-0-08046-911-9|url=https://books.google.com/books?id=Mwl3M6c5KzoC&pg=PA523}}</ref><ref>{{cite book|last=Rosenblum|first=Leonard A.|publisher=Elsevier Science|year = 2013|title=Primate Behavior: Developments in Field and Laboratory Research · Volume 2 |page=251|access-date=November 19, 2023|isbn=978-1-48327-182-8|url=https://books.google.com/books?id=QingBAAAQBAJ&pg=PA251}}</ref><ref>{{cite book|last=Poiani|first=Aldo|publisher=Cambridge University Press|year= 2010|title=Animal Homosexuality: A Biosocial Perspective|page=156|access-date=November 19, 2023|isbn=978-1-13949-038-2|url=https://books.google.com/books?id=EftT_1bsPOAC&pg=PA156}}</ref>

In non-primate female [[mammal]]s, the labia majora are absent since the labioscrotal swellings have disappeared as a fetus.<ref>{{cite book|last=Kumar|first=M.S.A.|publisher=Linus Learning|year = 2015| title=Clinically Oriented Anatomy of the Dog & Cat| page=1254|isbn=978-1-60797-552-6|url=https://books.google.com/books?id=ZBSSDwAAQBAJ&pg=PA1254}}</ref> Because of this, the pudendal cleft refers to the slit between the [[labia vulvae]] in those mammals.<ref>{{cite book |last1=Studdert | first1=Virginia P. |last2=Gray |first2=Clive C. | publisher=Elselvier Health Sciences |year=2011 | title=Saunders Comprehensive Veterinary Dictionary E-Book |page=1183 |isbn=978-0-70204-744-2|url=https://books.google.com/books?id=6dvQAQAAQBAJ&pg=PA1183}}</ref>

==Use in grafting==
The [[fat pad]] of the labia majora can be used as a [[graft (surgery)|graft]], often as a so-called "Martius labial fat pad graft", and can be used, for example, in [[urethrolysis]].<ref>{{Cite journal | last1 = Carey | first1 = J. M. | last2 = Chon | first2 = J. K. | last3 = Leach | first3 = G. E. | doi = 10.1016/S0090-4295(03)00117-1 | title = Urethrolysis with martius labial fat pad graft for iatrogenic bladder outlet obstruction | journal = Urology | volume = 61 | issue = 4 | pages = 21–25 | year = 2003 | pmid =  12657357}}</ref>

==See also==
* {{Portal inline|Anatomy}}
* ''[[Femalia]]''
* [[Labia pride]]
{{Clear|re=ight}}

==References==
{{Reflist}}

==External links==
{{Commons category|Labia majora}}
* [http://www.emedicinehealth.com/script/main/art.asp?articlekey=6190 Labia Majora Medical Definition] ({{Webarchive|url=https://web.archive.org/web/20160304203730/http://www.emedicinehealth.com/script/main/art.asp?articlekey=6190 |date=2016-03-04 }})

{{Women's health|state=collapsed}}
{{Female reproductive system}}
{{Authority control}}

{{DEFAULTSORT:Labia Majora}}
[[Category:Mammal female reproductive system]]
[[Category:Vulva]]

[[de:Schamlippe#Die großen (äußeren) Schamlippen]]