26.5F: Vulva
- Describe the structures and functions of the vulva
The vulva consists of the external genital organs of the female mammal. Its development occurs during several phases, chiefly during the fetal and pubertal periods. As the outer portal of the human uterus or womb, the vulva protects its opening with a “double door”: the labia majora (large lips) and the labia minora (small lips). The vulva also contains the opening of the female urethra, and thus serves the vital function of passing urine.
In human beings, major structures of the vulva are:
- The mons pubis
- The labia majora and the labia minora
- The external portion of the clitoris and the clitoral hood
- The vulval vestibule
- The pudendal cleft
- The frenulum labiorum pudendi or fourchette
- The opening (or urinary meatus) of the urethra
- The opening (or introitus) of the vagina
- The hymen
Other notable structures include:
- The perineum
- The sebaceous glands on labia majora
- The vaginal glands (Bartholin’s glands and paraurethral or Skene’s, glands)
Vulva : Labeled image of a vulva, showing external and internal views.
The soft mound at the front of the vulva, the mons pubis, is formed by fatty tissue covering the pubic bone. 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 the perineum, a flat area between the pudendal cleft and the anus. The color of the outside skin of the labia majora is usually close to the individual’s overall skin color 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, 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.
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, roughly the size and shape of a pea. 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. The clitoral hood is the female equivalent of the male foreskin and may be 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.
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 traditionally 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. 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.
Key Points
- Major structures of the vulva include the labia major and minora, mons pubis, clitoris, bulb of vestibule, vulva vestibule, vestibular glands, and the genital orifice (or opening of the vagina ).
- The vulva is rich in nerves that are stimulated during sexual activity and arousal.
- The vulva also contains the opening of the female urethra and thus serves the vital function of passing urine.
Key Terms
- labia minora : The two inner folds of skin within the cleft of the labia majora.
- vulva : The vaginal opening to the uterus.
- mons pubis : A fleshy protuberance over the pubic bones that becomes covered with hair during puberty.
- labia majora : The two outer rounded folds of adipose tissue that lie on either side of the opening of the vagina.