Vagina

The vagina, (from Latin, literally "sheath" or "scabbard" ) is the tubular tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles. Female insects and other invertebrates also have a vagina, which is the terminal part of the oviduct. The Latinate plural (rarely used in English) is vaginae.

In common speech, the term "vagina" is often used inaccurately to refer to the vulva or female genitals generally; strictly speaking, the vagina is a specific internal structure and the vulva is the exterior genitalia only.

Anatomy
The human vagina is an elastic muscular tube projecting inside a female. It is usually slightly shorter and thinner than an average male penis, at about 4 inches (100 mm) long and 1 inch (25 mm) in diameter (although there is wide anatomical variation) but its elasticity causes it to be able to accept larger penises and give birth to offspring. It connects the vulva at the outside to the cervix of the uterus on the inside. If the woman stands upright, the vaginal tube points in an upward-backward direction and forms an angle of slightly more than 45 degrees with the uterus. The vaginal opening is at the back (caudal) end of the vulva, behind the opening of the urethra. Above the vagina is Mons Veneris. The vagina, along with the inside of the vulva, is reddish pink in color, as with most healthy internal mucous membranes in mammals.

Length, width and shape of the vagina may vary. When a woman gives birth and during sexual intercourse, the vagina temporarily widens and lengthens.

Vaginal lubrication is provided by the Bartholin's glands near the vaginal opening and the cervix and also seeps through the vaginal wall (which does not contain any glands).

The hymen (a membrane situated at the opening of the vagina, which is also known as a maidenhead) partially covers it in many organisms, including many human females, from birth until it is ruptured by sexual intercourse, or by any number of other activities including medical examinations, injury, certain types of exercise, introduction of a foreign object, etc. However, it should be noted that sexual intercourse does not always cause the hymen to be broken, and so (for example) it is not true that a woman with an intact hymen must be a virgin or vice versa.

Functions of the vagina
From a biological perspective, the vagina performs the following functions:


 * Providing a path for menstrual fluids to leave the body.
 * Sexual activity
 * Giving birth

Menstruation
The vagina provides a path for menstrual fluids to leave the body. In modern societies, tampons, menstrual cups and sanitary towels may be used to absorb or capture these fluids.

Sexual activity
The concentration of the nerve endings that lie particularly close to the entrance of a woman's vagina can provide pleasurable sensation during sexual activity, when stimulated in a way that the particular woman enjoys. This activity may include heterosexual intercourse, during which a male partner's penis is placed within the vagina, manual stimulation (either self, or partner), or other stimulation such as tribadism. An erogenous zone referred to commonly as the G-spot is located at the anterior wall of the vagina, about five centimeters in from the entrance. Some women can experience very intense pleasure if the G-spot is stimulated appropriately during intercourse or other sexual activity. A G-Spot orgasm may be responsible for female ejaculation.

Giving birth
During childbirth, the vagina provides the route to deliver the baby from the uterus to its independent life outside the body of the mother. During birth, the vagina is often referred to as the birth canal. The vagina can stretch greatly to ensure sucessful delivery of the baby.

Sexual health and hygiene
The vagina is a self-cleaning organ and needs no special treatment. Doctors discourage Douching, which upsets the balance of vaginal flora and may cause infection and other problems.

The vagina is examined during gynecological exams, often using a speculum, which keeps the vagina open for visual inspection of the cervix or taking of samples (see pap smear).

Vulvovaginal disorders can affect the vagina, including vaginal cancer and yeast infections.

The vagina and popular culture
Western society treats the term and subject of the vagina as somewhat taboo. A one-person play by Eve Ensler known as The Vagina Monologues is a rare example of the word appearing in mainstream culture, although the play continues to remain the target of censorship conflicts.