The
hymen is a
membrane-In biology:* Biological membrane* Cell membrane, a biological type of Membrane ** Inner membrane** Outer membrane * The two fetal membranes** amnion** chorion* Basement membrane* Mucous membrane* Serous membrane...
that surrounds or partially covers the external
vaginaThe vagina is a fibromuscular 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...
l opening. It forms part of the
vulvaThe vulva 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....
, or external genitalia. The size of the hymenal opening increases with age. Although an often practiced method, it is not possible to confirm with certainty that a girl or woman is a
virginVirginity refers to the state of a person who has never engaged in sexual intercourse. There are cultural and religious traditions which place special value and significance on this state, especially in the case of unmarried females, associated with notions of personal purity, honor and worth...
by examining her hymen. In cases of suspected
rapeRape is a type of sexual assault usually involving sexual intercourse, which is initiated by one or more persons against another person without that person's consent. The act may be carried out by physical force, coercion, abuse of authority or with a person who is incapable of valid consent. The...
or
child sexual abuseChild sexual abuse is a form of child abuse in which an adult or older adolescent uses a child for sexual stimulation. Forms of child sexual abuse include asking or pressuring a child to engage in sexual activities , indecent exposure with intent to gratify their own sexual desires or to...
, a detailed examination of the hymen may be performed, but the condition of the hymen alone is often inconclusive. In younger children, a torn hymen will typically heal very quickly. In adolescents, the hymenal opening does extend from natural causes and variation in shape and appearance increases. In children, although a common appearance of the hymen is
crescentIn art and symbolism, a crescent is generally the shape produced when a circular disk has a segment of another circle removed from its edge, so that what remains is a shape enclosed by two circular arcs of different diameters which intersect at two points .In astronomy, a crescent...
-shaped, many variations are possible. After a woman
gives birthChildbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...
, she may be left with remnants of the hymen, called
carunculae myrtiformes, or the hymen may be completely absent.
The
hymen is a
membrane-In biology:* Biological membrane* Cell membrane, a biological type of Membrane ** Inner membrane** Outer membrane * The two fetal membranes** amnion** chorion* Basement membrane* Mucous membrane* Serous membrane...
that surrounds or partially covers the external
vaginaThe vagina is a fibromuscular 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...
l opening. It forms part of the
vulvaThe vulva 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....
, or external genitalia. The size of the hymenal opening increases with age. Although an often practiced method, it is not possible to confirm with certainty that a girl or woman is a
virginVirginity refers to the state of a person who has never engaged in sexual intercourse. There are cultural and religious traditions which place special value and significance on this state, especially in the case of unmarried females, associated with notions of personal purity, honor and worth...
by examining her hymen. In cases of suspected
rapeRape is a type of sexual assault usually involving sexual intercourse, which is initiated by one or more persons against another person without that person's consent. The act may be carried out by physical force, coercion, abuse of authority or with a person who is incapable of valid consent. The...
or
child sexual abuseChild sexual abuse is a form of child abuse in which an adult or older adolescent uses a child for sexual stimulation. Forms of child sexual abuse include asking or pressuring a child to engage in sexual activities , indecent exposure with intent to gratify their own sexual desires or to...
, a detailed examination of the hymen may be performed, but the condition of the hymen alone is often inconclusive. In younger children, a torn hymen will typically heal very quickly. In adolescents, the hymenal opening does extend from natural causes and variation in shape and appearance increases. In children, although a common appearance of the hymen is
crescentIn art and symbolism, a crescent is generally the shape produced when a circular disk has a segment of another circle removed from its edge, so that what remains is a shape enclosed by two circular arcs of different diameters which intersect at two points .In astronomy, a crescent...
-shaped, many variations are possible. After a woman
gives birthChildbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...
, she may be left with remnants of the hymen, called
carunculae myrtiformes, or the hymen may be completely absent.
Development
The
genital tract developsThe development of the reproductive system is a part of prenatal development, and concerns the sex organs. It is a part of the stages of sexual differentiation...
during embryogenesis, from the third week of gestation to the second trimester, and the hymen is formed following the vagina.
At week seven, the urorectal septum forms and separates the rectum from the urogenital sinus.
At week nine, the müllerian ducts move downwards to reach the urogenital sinus, forming the uterovaginal canal and inserting into the urogenital sinus.
At week 12, the müllerian ducts fuse to create a primitive uterovaginal canal called unaleria
At month 5, the vaginal canalization is complete and the fetal hymen is formed from the proliferation of the sinovaginal bulbs (where müllerian ducts meet the urogenital sinus), and becomes perforate before or shortly after birth.
In newborn babies, still under the influence of the mother's hormones, the hymen is thick, pale pink, and redundant (folds in on itself and may protrude). For the first two to four years of life, the infant produces hormones that continue this effect. Their hymenal opening tends to be annular (circumferential).
Resorption
Past neonatal stage, the diameter of the hymenal opening (measured within the hymenal ring) has been proposed to be approximately 1 mm for each year of age. In children, to make this measurement, a doctor may place a
Foley catheterA Foley catheter is a flexible tube that is often passed through the urethra and into the bladder. The tube has two separated channels, or lumens, running down its length. One lumen is open at both ends, and allows urine to drain out into a collection bag...
into the vagina and inflate the balloon behind the hymen to stretch the hymenal margin and allow for a better examination. In the normal course of life, the hymenal opening can also be enlarged by
tamponA tampon is a mass of cotton or rayon or a mixture of the two inserted into a body cavity or wound to absorb bodilyfluid. The most common type in daily use is designed to be inserted into the vagina during menstruation to absorb the flow of menstrual fluid...
or
menstrual cupA menstrual cup is a type of cup or barrier worn inside the vagina during menstruation to collect menstrual fluid. Unlike tampons and pads, the cup collects menstrual fluid rather than absorbing it...
use, pelvic examinations with a
speculumA speculum is a medical tool for investigating body cavities, with a form dependent on the body cavity for which it is designed. In old texts, the speculum may also be referred to as a diopter or dioptra...
, regular physical activity or sexual intercourse. Once a girl reaches puberty, the hymen tends to become so elastic that it is not possible to determine whether a woman uses tampons or not by examining her hymen. In one survey, only 43% of women reported bleeding the first time they had intercourse, indicating that the hymens of a majority of women are sufficiently opened.
The hymen is most apparent in young girls: At this time, their hymen is thin and less likely to be
redundant, that is to protrude or fold over on itself. In instances of suspected child abuse, doctors use the
clock faceA clock face is the part of an analog clock that displays the time through the use of a fixed numbered dial or dials and moving hands. In its most basic form, recognized universally throughout the world, the dial is numbered 1–12 indicating the hours in a 12-hour cycle, and a short hour hand...
systemClock position is a way of communicating the relative direction of an object using the analogy of a 12-hour clock. One imagines a clock face lying either upright or flat in front of oneself, and identifies the twelve hour markings with the directions in which they point.Using this analogy, 12...
to describe the hymenal opening. The 12 o'clock position is below the
urethraIn anatomy, the urethra is a tube that connects the urinary bladder to the genitals for the removal of fluids out of the body. In males, the urethra travels through the penis, and carries semen as well as urine...
, and 6 o'clock is towards the
anusThe anus is an opening at the opposite end of an animal's digestive tract from the mouth. Its function is to control the expulsion of feces, unwanted semi-solid matter produced during digestion, which, depending on the type of animal, may be one or more of: matter which the animal cannot digest,...
, with the patient lying on her back.
Infants' hymenal openings tend to be redundant (sleeve-like, folding in on itself), and may be ring-shaped.
By the time a girl reaches school age, this hormonal influence has ceased, and the hymen becomes thin, smooth, delicate, and nearly translucent. It is also very sensitive to touch; a physician who must swab the area should avoid the hymen and swab the outer
vulval vestibuleThe Vulval vestibule is a part of the vulva between the labia minora into which the urethral opening and the vaginal opening open...
instead.
Prepubescent girls' hymenal openings come in many shapes, depending on hormonal and activity level, the most common being crescentic (posterior rim): no tissue at the 12 o'clock position; crescent-shaped band of tissue from 1–2 to 10–11 o'clock, at its widest around 6 o'clock. From puberty onwards, depending on
estrogenEstrogens , oestrogens , or œstrogens, are a group of compounds named for their importance in the estrous cycle of humans and other animals. They are the primary female sex hormones. Natural estrogens are steroid hormones, while some synthetic ones are non-steroidal...
and activity levels, the hymenal tissue may be thicker, and the opening is often fimbriated or erratically shaped.
After giving birth, the vaginal opening usually has nothing left but hymenal tags (carunculae myrtiformes) and is called "parous introitus".
Anatomic anomalies
Anomalies of the female reproductive tract can result from
agenesisMüllerian agenesis is a congenital malformation in women characterised by a failure of the müllerian ducts to develop, resulting in a missing uterus and fallopian tubes and variable malformations of the upper portion of the vagina. It is the second most common cause of primary amenorrhea after...
or hypoplasia, canalization defects, lateral fusion and failure of resorption, resulting in various complications.
- Imperforate: hymenal opening nonexistent; will require minor surgery if it has not corrected itself by puberty to allow menstrual fluids to escape.
- Cribriform, or microperforate: sometimes confused for imperforate, the hymenal opening appears to be nonexistent, but has, under close examination, small openings.
- Septate: the hymenal opening has one or more bands of tissue extending across the opening.
Hymenorrhaphy
In some cultures, an intact hymen is highly valued at marriage mainly to show
virginityVirginity refers to the state of a person who has never engaged in sexual intercourse. There are cultural and religious traditions which place special value and significance on this state, especially in the case of unmarried females, associated with notions of personal purity, honor and worth...
. Some women undergo hymenoplasty, a restoration of their hymen for this reason.
Womb fury
In the sixteenth and seventeenth centuries, medical researchers used the presence of the hymen, or lack thereof, as founding evidence of physical diseases such as "womb-fury" (
hysteriaHysteria, in its colloquial use, describes unmanageable emotional excesses. People who are "hysterical" often lose self-control due to an overwhelming fear that may be caused by multiple events in one's past that involved some sort of severe conflict; the fear can be centered on a body part, or,...
). If not cured, womb-fury would, according to these early doctors, result in death.
In other animals
Due to similar reproductive system development, many mammals, including chimpanzees, elephants, manatees, whales, and horses retain hymens.
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