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The vulva (from the Latin ''vulva'', plural ''vulvae'', see etymology) consists of the external genital organs of the female mammal. This article deals with the vulva of the human being, although the structures are similar for other mammals. The vulva has many major and minor anatomical structures, including the labia majora, mons pubis, labia minora, clitoris, bulb of vestibule, vulval vestibule, greater and lesser vestibular glands, external urethral orifice and the opening of the vagina (introitus). Its development occurs during several phases, chiefly during the fetal and pubertal periods of time. As the outer portal of the human uterus or womb, it protects its opening by a "double door": the labia majora (large lips) and the labia minora (small lips). The vagina is a self-cleaning organ, sustaining healthy microbial flora that flow from the inside out; the vulva needs only simple washing to assure good vulvovaginal health, without recourse to any internal cleansing. The vulva has a sexual function; these external organs are richly innervated and provide pleasure when properly stimulated. In various branches of art, the vulva has been depicted as the organ that has the power both to "give life" (often associated with the womb), and to give sexual pleasure to humankind. The vulva also contains the opening of the female urethra, but apart from this has little relevance to the function of urination. ==Structure== In humans, major structures of the vulva are: * the mons pubis * the labia, consisting of the labia majora and the labia minora * the external portion of the clitoris, consisting of the clitoral glans and the clitoral hood * the urinary meatus (opening of the urethra) * the vaginal orifice (opening of the vagina) * the hymen Other structures: * the vulval vestibule * the pudendal cleft * the frenulum labiorum pudendi or the ''fourchette'' * the perineum * the sebaceous glands on labia majora * the vaginal glands: * * Bartholin's glands * * Paraurethral glands called Skene's glands 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 it 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 mucous 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, color, 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 may 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.〔(A Surgical Temptation: The Demonization of the Foreskin and the Rise of Circumcision in Britain, Darby )〕 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 urinary bladder to be disposed of. 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 (including horseback riding) or be stretched by normal activities such as use of tampons and menstrual cups, or be so minor as to be unnoticeable. In some rare cases, the hymen may completely cover the vaginal opening, requiring a surgical incision. 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 yet 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. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Vulva」の詳細全文を読む スポンサード リンク
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