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Vulva
Illu repdt female
Latin '
Gray's subject #270 1264
System
MeSH 05.360.319.887
Illu female genitalia
{{{Caption2}}}

The external genital organs of the female are collectively known as the vulva (plural vulvae, vulvas). In common speech, the term vagina is often used improperly to refer to the vulva or female genitals generally - even though strictly speaking the vagina is a specific internal structure and the vulva is the exterior genitalia only.

Etymology[]

The word "vulva" was taken from Middle Latin volva or vulva "womb, female genitals", probably from Latin volvere "to roll". Similar to Sanskrit ulva "womb".

Structures[]

File:Vulva labeled english.jpg

Vulva structures labeled with anus

In human beings, major structures of the vulva are:[1]

  • the mons pubis
  • the labia, consisting of the labia majora and the labia minora
  • the external portion of the clitoris (Latin: Clitoral glans) and the clitoral hood
  • the vulval vestibule
  • the cleft of venus
  • the frenulum labiorum pudendi or the fourchette
  • the opening (or urinary meatus) of the urethra
  • the opening (or introitus) of the vagina
  • the hymen and

Other structures:

File:Pubic hair.jpg

Vulva with pubic hair

The soft mound at the front of the vulva is formed by fatty tissue covering the pubic bone, and is called the mons pubis. The term mons pubis is Latin for "pubic mound" and is gender-nonspecific. There is, however, a variant term that specifies gender: in human females, the mons pubis is often referred to as the mons veneris, Latin for "mound of Venus" or "mound of love". The mons pubis separates into two folds of skin called the labia majora, literally "major (or large) lips". The cleft between the labia majora is called the pudendal cleft, or cleft of Venus, and it contains and protects the other, more delicate structures of the vulva. The labia majora meet again at a flat area between the pudendal cleft and the anus called the perineum. The color of the outside skin of the labia majora is usually close to the overall skin color of the individual, although there is considerable variation. The inside skin and mucus membrane are often pink or brownish. After the onset of puberty, the mons pubis and the labia majora become covered by pubic hair. This hair sometimes extends to the inner thighs and perineum, but the density, texture, and extent of pubic hair coverage vary considerably, due to both individual variation and cultural practices of hair modification or removal.

The labia minora are two soft folds of skin within the labia majora. While labia minora translates as "minor (or small) lips", often the "minora" are of considerable size, and protrude outside the "majora". Much of the variation among vulvas lies in the significant differences in the size, shape, and color of the labia minora

The clitoris is located at the front of the vulva, where the labia minora meet. The visible portion of the clitoris is the clitoral glans. Typically, the clitoral glans is roughly the size and shape of a pea, although it can be significantly larger or smaller. The clitoral glans is highly sensitive, containing as many nerve endings as the analogous organ in males, the glans penis. The point where the labia minora attach to the clitoris is called the frenulum clitoridis. A prepuce, the clitoral hood, normally covers and protects the clitoris, however in women with particularly large clitorises or small prepuces, the clitoris may be partially or wholly exposed at all times. The clitoral hood is the female equivalent of the male foreskin.[2] Often the clitoral hood is only partially hidden inside of the pudendal cleft.

The area between the labia minora is called the vulval vestibule, and it contains the vaginal and urethral openings. The urethral opening (meatus) is located below the clitoris and just in front of the vagina. This is where urine passes from the bladder to the outside of the body.

The opening of the vagina is located at the bottom of the vulval vestibule, toward the perineum. The term introitus is more technically correct than "opening", since the vagina is usually collapsed, with the opening closed, unless something is inserted. The introitus is sometimes partly covered by a membrane called the hymen. The hymen will rupture during the first episode of vigorous sex, and the blood produced by this rupture has been seen as a sign of virginity. However, the hymen may also rupture spontaneously during exercise or be stretched by normal activities such as use of tampons, or be so minor as to be unnoticeable. In some rare cases, the hymen may completely cover the vaginal opening, requiring surgical separation. Slightly below and to the left and right of the vaginal opening are two Bartholin glands which produce a waxy, pheromone-containing substance, the purpose of which is not fully known.

The appearance of the vulva and the size of the various parts varies a great deal from one female to another, and it is also common for the left and right sides to differ in appearance.

Development[]

Fetus[]

File:Genital tubercle 14 weeks.JPG

Genital tubercle at fourteen weeks.

During the first eight weeks of life, both male and female fetuses have the same rudimentary reproductive and sexual organs, and maternal hormones control their development. Male and female organs begin to become distinct when the fetus is able to begin producing its own hormones, although visible determination of the sex is difficult until after the twelfth week.

During the sixth week, the genital tubercle develops in front of the cloacal membrane. The tubercle contains a groove termed the urethral groove. The urogenital sinus (forerunner of the bladder) opens into this groove. On either side of the groove are the urogenital folds. Beside the tubercle are a pair of ridges called the labioscrotal swellings.

Beginning in the third month of development, the genital tubercle becomes the clitoris. The urogenital folds become the labia minora, and the labioscrotal swellings become the labia majora.

Childhood[]

At birth, the neonate's vulva (and breast tissue—see witch's milk) may be swollen or enlarged as a result of having been exposed, via the placenta, to her mother's increased levels of hormones. The clitoris is proportionally larger than it is likely to be later in life. Within a short period of time as these hormones wear off, the vulva will shrink in size.

From one year of age until the onset of puberty, the vulva does not undergo any change in appearance, other than growing in proportion with the rest of the body.

Puberty[]

The onset of puberty produces a number of changes. The structures of the vulva become proportionately larger and may become more pronounced. Coloration may change and pubic hair develops, first on the labia majora, and later spreading to the mons pubis, and sometimes the inner thighs and perineum.

In preadolescent girls, the vulva appears to be positioned further forward than in adults, showing a larger percentage of the labia majora and pudendal cleft when standing. During puberty the mons pubis enlarges, pushing the forward portion of the labia majora away from the pubic bone, and parallel to the ground (when standing). Variations in body fat levels affect the extent to which this occurs.

Childbirth[]

During childbirth, the vagina and vulva must stretch to accommodate the baby's head (approximately 9.5 cm or 3.7 in). This can result in tears in the vaginal opening, labia, and clitoris. An episiotomy (surgical preemptive cutting of the perineum) is sometimes performed to limit tearing, but its appropriateness as a routine procedure is under debate.

Some of the changes that occur during pregnancy may be permanent.

Post-menopause[]

During menopause, hormone levels decrease, and as this process happens, reproductive tissues which are sensitive to these hormones shrink in size. The mons pubis, labia, and clitoris are reduced in size in post-menopause, although not usually to pre-puberty proportions.

Sexual arousal[]

Main article: Human sexual response cycle

Sexual arousal results in a number of physical changes in the vulva. Arousal may be broken up into four somewhat arbitrary phases: Excitement, Plateau, Orgasm, and Resolution.

File:Female sexual arousal.JPG

In the left image female genitalia are in the resting state. In the right image the female is sexually aroused, the vulva is wet and the labia are slightly swollen.

Excitement[]

Vaginal lubrication begins first. This is caused by the vasocongestion of the vaginal walls. Increased blood pooling there causes moisture to seep from the walls. These droplets collect together and flow out of the vagina, moistening the vulva. The labia majora flatten and spread apart, and the clitoris and labia minora increase in size.

Unlike in men, where sexual excitement produces large and readily apparent changes, namely an erection, women are not necessarily aware that vaginal lubrication and blood engorgement of their vaginas have occurred.

Plateau[]

Increased vasocongestion in the vagina causes it to swell, decreasing the size of the vaginal opening by about 30%. The clitoris becomes increasingly erect, and the glans moves towards the pubic bone, becoming concealed by the hood. The labia minora increase considerably in thickness, approximately 2–3 times, causing them to spread apart, displaying the vaginal opening. The labia minora change considerably in color, going from pink to red in Caucasian women who have not borne a child, or red to dark red in those that have[3].

Orgasm[]

Immediately prior to orgasm, the clitoris becomes exceptionally engorged, causing the glans to appear to retract into the clitoral hood. This is thought to protect the sensitive glans during orgasm. However, there is some doubt that this is the case, since the same engorgement prior to orgasm occurs in the male homologous structure, the penis, the function of which is thought to be to extend the penis as close to the cervix as possible prior to ejaculation.

Rhythmic muscle contractions occur in the outer third of the vagina, as well as the uterus and anus. They occur initially at a rate of about one every 0.8 seconds, becoming less intense and more randomly spaced as the orgasm continues. An orgasm may have as few as one or as many as 15 or more contractions, depending on intensity. Orgasm may be accompanied by female ejaculation, causing liquid from either the Skene's gland or bladder to be expelled through the urethra.

Immediately after orgasm the clitoris may be so sensitive that any stimulation is uncomfortable.

Resolution[]

The pooled blood begins to dissipate, although at a much slower rate if orgasm has not occurred. The vagina and vaginal opening return to their normal relaxed state, and the rest of the vulva returns to its normal size, position and color.

Fluids and odor[]

There are a number of different secretions associated with the vulva, including urine, sweat, menses, skin oils (sebum), Bartholin's and Skene's gland secretions, and vaginal wall secretions. These secretions contain a mix of chemicals, including pyridine, squalene, urea, acetic acid, lactic acid, complex alcohols, glycols, ketones, and aldehydes. During sexual arousal, vaginal lubrication increases.

Smegma[]

Smegma is a white substance formed from a combination of dead cells, skin oils, moisture and naturally occurring bacteria, that forms in mammalian genitalia. In females it collects around the clitoris and labial folds.

Aliphatic acids[]

Approximately one third of women produce aliphatic acids. These acids are a pungent class of chemicals which other primate species produce as sexual-olfactory signals. While there is some debate, researchers often refer to them as human pheromones. These acids are produced by natural bacteria resident on the skin. The acid content varies with the menstrual cycle, rising from one day after menstruation, and peaking mid-cycle, just before ovulation.



Disorders affecting the vulva[]

Blemishes and Cysts[]

  • Epidermal Cysts
  • Angiomas
  • Moles
  • Freckles
  • Lentigos

Infections[]

  • Candidiasis (thrush)
  • Bacterial vaginosis (BV)
  • Warts (due to HPV or condyloma acuminata)
  • Molluscum contagiosum
  • Herpes Simplex (genital herpes)
  • Herpes Zoster (shingles)
  • Tinea (fungus)
  • Hidradenitis suppurativa

Inflammatory Diseases[]

  • Eczema/Dermatitis
  • Lichen simplex (chronic eczema)
  • Psoriasis
  • Lichen sclerosus
  • Lichen planus
  • zoons vulvitis (zoons balanitis in men)
  • Pemphigus vulgaris
  • Pemphigoid (mucous membrane pemphigoid, cicratricial pemphigoid, bullous pemphigoid)

Pain Syndromes[]

Vulvar Cancer[]

  • Squamous cell carcinoma (the most common kind)
  • Basal cell carcinoma
  • Melanoma

Ulcers[]

  • Aphthous ulcer
  • Behcet's Disease

Developmental Disorders[]

  • Septate vagina
  • Vaginal opening extremely close to the urethra or anus
  • An imperforate hymen
  • Various stages of genital masculinization including fused labia, an absent or partially-formed vagina, urethra located on the clitoris.
  • Hermaphroditism

Other[]

  • Vulvar lymphangioma
  • Paget's disease
  • Vulvar intraepithelial neoplasia (VIN)
  • Bowen's disease
  • Bowenoid papulosis
  • Vulvar varicose veins
  • Labial adhesions
  • Perineodynia (perineal pain)
  • Desquamative Inflammatory Vaginitis (DIV)
  • Childbirth tears and Episiotomy related changes

Altering the female genitalia[]

Main article: Genital modification and mutilation
File:Intimpiercing Frau Klit vorhaut.jpg

Horizontal clitoral hood piercing.

The most prevalent form of genital alteration in some countries is female genital cutting: removal of any part of the female genitalia for cultural, religious or other non-medical reasons. When performed on female minors these procedures can be highly controversial. In some cases, people elect to have their genitals pierced, tattooed or otherwise altered for aesthetic or other reasons. Female genital enhancement surgery includes laser resurfacing of the labia to remove wrinkles and clitoral repositioning for those not achieving optimum stimulation as well as labiaplasty and vaginal tightening.

Cultural attitudes[]

In some cultures, including modern Western culture, some women have shaved or otherwise depilated part or all of the vulva. This is a fairly recent phenomenon in the United States, but has been prevalent, usually in the form of waxing, in many eastern European and Middle Eastern cultures for centuries, usually for the purpose of hygiene. High-cut swimsuits compelled their wearers to shave the sides of their pubic triangles. Shaving may also include all or nearly all of the hair. Some styles retain a "racing stripe" (on either side of the labia) or "landing strip" (directly above and in line with the vulva). See the article on pubic hair.

Since the early days of Islam, Muslim women and men have followed a tradition to "pluck the armpit hairs and shave the pubic hairs". This is a preferred practice rather than an obligation, and could be carried out by shaving, waxing, trimming, or any other shaving method. This is a regular practice that is considered in some more devout Muslim cultures as a form of worship, not a shameful practice, while in other less devout regions it is a practice for the purpose of good hygiene. The reasons behind removing this hair could also be applied to the hair on the scrotum and around the anus, because the purpose is to be completely clean and pure and keep away from anything that may cause dirt and impurities according to Al-Munajjid, Sheikh Muhammad Saleh (Released 27th July 2004). "Islam Ruling on Shaving the Pubic Hair, Scrotum and Around the Anus".

Many cultures have commonly viewed the vulva as something shameful that should be hidden; for example, the term pudendum, which denotes the external genitalia, literally means "shameful thing." However, some cultures have celebrated and even worshipped the vulva; some Hindu sects revere it under the name yoni,[How to reference and link to summary or text] and texts seem to indicate a similar attitude in some ancient Middle Eastern religions. As an aspect of Goddess worship such reverence may be part of modern Neopagan beliefs, and may be indicated in paleolithic artworks. Other cultures consider some or all parts of the vulva to be "unclean" and may go as far as to advocate female "circumcision".

Many sculptors and painters have chosen not to display vulvas in their works, even when depicting nude women. The pubic region was often covered with a piece of cloth, figleaf or a hand. When it was displayed or posed, it usually lacked pubic hair (see glabrousness) as well as the physical depiction of the vulva, irrespective of whether the vulva would actually be visible in that pose. In modern times Japanese anime artists often depict female characters without vulvas (even in hentai pornography) to comply with censorship laws.

As throughout history the actual or artistic display of vulvas was uncommon, aesthetic standards for the depiction of the vulva in the West developed after visual pornography became more widespread.[How to reference and link to summary or text] Currently, color desaturation is often used to purge photographic images of pornographic associations.

See also[]

  • Vulvovaginal health
  • Gonad


External links[]


  1. Glossary
  2. Darby, Robert|"A Surgical Temptation"|http://www.press.uchicago.edu/presssite/metadata.epl?isbn=9780226136455
  3. citation needed
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