Hymen

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"Himen" redirects here. For the village in Iran, see Himen, Iran.
This article is about the vaginal membrane. For the god and other uses, see Hymen (disambiguation).
Hymen
Gray1229.png
External genital organs of female. The labia minora have been drawn apart.
Details
Latin hymen vaginae
Identifiers
Gray's p.1264
MeSH A05.360.319.779.479
TA A09.1.04.008
FMA FMA:20005
Anatomical terminology

The hymen is a membrane that surrounds or partially covers the external vaginal opening. It forms part of the vulva, or external genitalia, and is similar in structure to the vagina.[1][2] In children, although a common appearance of the hymen is crescent-shaped, many shapes are possible.[1]

The effects of sexual intercourse and childbirth on the hymen are variable. If the hymen is sufficiently elastic, it may return to nearly its original condition. In other cases, there may be remnants (carunculae myrtiformes), or it may appear completely absent after repeated penetration.[3][4] Additionally, the hymen may be lacerated by disease, injury, medical examination, masturbation or even physical exercise. For these reasons, the state of the hymen is not a conclusive indicator of virginity.[2][3][4]

A glass or plastic rod of 6 mm diameter having a globe on one end with varying diameter from 10 to 25 mm, called Glaister Keen rod, is used for close examination of hymen or the degree of its rupture.

Development[edit]

The genital tract develops 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.[5] Their hymenal opening tends to be annular (circumferential).[6]

By the time a girl reaches school age,[clarification needed] the hymen becomes thin, smooth, delicate, and nearly translucent. It is also very sensitive to touch; in forensic medicine, a physician who must swab this area of a prepubescent girl should avoid the hymen and swab the outer vulval vestibule instead.[5]

Past neonatal stage, the diameter of the hymenal opening (measured within the hymenal ring) widens by approximately 1 mm for each year of age.[7] During puberty the hymenal opening can also be enlarged by tampon or menstrual cup use, pelvic examinations with a speculum, regular physical activity or sexual intercourse.[1] Once a girl reaches puberty, the hymen tends to become very elastic. 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 open to prevent tearing.[1][5]

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 estrogen and activity levels, the hymenal tissue may be thicker, and the opening is often fimbriae of uterine tube or erratically shaped.[6] In cases of suspected rape or child sexual abuse, 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 can naturally extend and variation in shape and appearance increases.[1]

After giving birth, the vaginal opening usually has nothing left but hymenal tags (carunculae myrtiformes) and is called parous introitus.

Anatomic anomalies[edit]

Various types of hymen (the dark areas represent the vaginal opening)

Anomalies of the female reproductive tract can result from agenesis or hypoplasia, canalization defects, lateral fusion and failure of resorption, resulting in various complications.[7]

  • Imperforate:[8][9] 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 perforations.
  • Septate: the hymenal opening has one or more bands of tissue extending across the opening.

Hymenorrhaphy[edit]

Main article: Hymenorrhaphy
See also: Virginity fraud

In some cultures, an intact hymen is highly valued at marriage in the belief that this is a proof of virginity.[10][11][12] Some women undergo hymenorrhaphy, a restoration of their hymen for this reason.[12][13]

Womb fury[edit]

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", i.e. (female) hysteria. If not cured, womb-fury would, according to these early doctors, result in death.[14][15]

Other animals[edit]

Due to similar reproductive system development, many mammals, including chimpanzees, elephants, manatees, whales, and horses retain hymens.[16][17]

See also[edit]

References[edit]

  1. ^ a b c d e Emans, S. Jean. "Physical Examination of the Child and Adolescent" (2000) in Evaluation of the Sexually Abused Child: A Medical Textbook and Photographic Atlas, Second edition, Oxford University Press. 61-65
  2. ^ a b Perlman, Sally E.; Nakajyma, Steven T. and Hertweck, S. Paige (2004). Clinical protocols in pediatric and adolescent gynecology. Parthenon. p. 131. ISBN 1-84214-199-6. 
  3. ^ a b Knight, Bernard (1997). Simpson's Forensic Medicine (11th ed.). London: Arnold. p. 114. ISBN 0-7131-4452-1. 
  4. ^ a b Jacoby, David B.; Youngson, Robert M. (2005). Encyclopedia of Family Health (3rd ed.). Marshall Cavendish. p. 889. ISBN 0-7614-7486-2. 
  5. ^ a b c McCann, J; Rosas, A. and Boos, S. (2003) "Child and adolescent sexual assaults (childhood sexual abuse)" in Payne-James, Jason; Busuttil, Anthony and Smock, William (eds). Forensic Medicine: Clinical and Pathological Aspects, Greenwich Medical Media: London, a)p.453, b)p.455 c)p.460.
  6. ^ a b Heger, Astrid; Emans, S. Jean and Muram, David (2000). Evaluation of the Sexually Abused Child: A Medical Textbook and Photographic Atlas (Second ed.). Oxford University Press. p. 116. ISBN 0-19-507425-4. 
  7. ^ a b "Imperforate Hymen". Web MD. Retrieved 2009-02-02. Different normal variants in hymenal configuration are described, varying from the common annular, to crescentic, to navicular ("boatlike" with an anteriorly displaced hymenal orifice). Hymenal variations are rarely clinically significant before menarche. In the case of a navicular configuration, urinary complaints (e.g., dribbling, retention, urinary tract infections) may result. Sometimes, a cribriform (fenestrated), septate, or navicular configuration to the hymen can be associated with retention of vaginal secretions and prolongation of the common condition of a mixed bacterial vulvovaginitis. 
  8. ^ Steinberg, Avraham; Rosner, Fred (2003). Encyclopedia of Jewish Medical Ethics. ISBN 1-58330-592-0. Occasionally, the hymen is harder than normal or it is complete and sealed without there being ... This condition is called imperforate hymen and, at times ... 
  9. ^ DeCherney, Alan H.; Pernoll, Martin L. and Nathan, Lauren (2002). Current Obstetric & Gynecologic Diagnosis & Treatment. McGraw-Hill Professional. p. 602. ISBN 0-8385-1401-4. Imperforate hymen represents a persistent portion of the urogenital membrane ... It is one of the most common obstructive lesions of the female genital tract. ... 
  10. ^ "Muslim women in France regain virginity in clinics". Reuters. 2007-04-30. 'Many of my patients are caught between two worlds,' said Abecassis. They have had sex already but are expected to be virgins at marriage according to a custom that he called 'cultural and traditional, with enormous family pressure'. 
  11. ^ "The Hymen". University of California at Santa Barbara. Retrieved 2009-02-09. The hymen can have very important cultural significance in certain cultures because of its association with a woman’s virginity. 
  12. ^ a b Sciolino, Elaine; Mekhennet, Souad (June 11, 2008). "In Europe, Debate Over Islam and Virginity". The New York Times. Retrieved 2008-06-13. 'In my culture, not to be a virgin is to be dirt,' said the student, perched on a hospital bed as she awaited surgery on Thursday. 'Right now, virginity is more important to me than life.' 
  13. ^ Hymenoplasty is depicted in a fictional context in "Everett Poe", an episode of the television series Nip/Tuck that was broadcast in 2007.
  14. ^ Berrios GE, Rivière L. (2006) 'Madness from the womb'. History of Psychiatry. 17:223-35.
  15. ^ The linkage between the hymen and social elements of control has been taken up in Marie Loughlin's book Hymeneutics: Interpreting Virginity on the Early Modern Stage published in 1997
  16. ^ Blank, Hanne (2007). Virgin: The Untouched History. Bloomsbury Publishing. p. 23. ISBN 1-59691-010-0. Retrieved 2013-11-09. 
  17. ^ Blackledge, Catherine (2004). The Story of V. Rutgers University Press. ISBN 0-8135-3455-0. Hymens, or vaginal closure membranes or vaginal constrictions, as they are often referred to, are found in a number of mammals, including llamas, ... 

External links[edit]