Biology:Hymen

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Hymen
Gray1229.png
External genital organs of female. The labia minora have been drawn apart.
Details
Identifiers
Latinhymen vaginae
Anatomical terminology

The hymen is a thin piece of mucosal tissue 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] The hymen does not seem to have a specific physiological function and has few, if any, nerve endings.[3]

In children, a common appearance of the hymen is crescent-shaped, although many shapes are possible. During puberty, estrogen causes the hymen to change in appearance[3] and become very elastic.[4][5] Normal variations of the post-pubertal hymen range from thin and stretchy to thick and somewhat rigid; or it may instead be completely absent.[1]

The hymen may rip or tear the first time penetrative intercourse happens, which may cause temporary bleeding or slight discomfort, but sources differ on how common tearing and bleeding after first intercourse is.[6][7][8] The state of the hymen is not a reliable indicator of virginity,[2][9] although it continues to be considered so in certain cultures, and virginity testing may be done. Minor injuries to the hymen may heal[10] without visible signs of previous injury. A torn hymen may be surgically restored in a procedure called hymenorrhaphy.

Development and histology

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 twelve, the Müllerian ducts fuse to create a primitive uterovaginal canal called unaleria. At month five, 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 normally becomes perforate before or shortly after birth.[11]

The hymen has no nerve innervation. 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.[12] Their hymenal opening tends to be annular (circumferential).[13]

Past neonatal stage, the diameter of the hymenal opening (measured within the hymenal ring) widens by approximately 1 mm for each year of age.[14] During puberty, estrogen causes the hymen to become very elastic and fimbriated.[4][5]

  • A post-pubertal hymen. Appearance is highly variable.

  • Arrows point to carunculae myrtiformes ("remnants") of the hymen in a post-pubertal individual.

The hymen can stretch or tear as a result of various behaviors, by tampon or menstrual cup use, pelvic examinations with a speculum, regular physical activity, sexual intercourse,[1] insertion of multiple fingers or items into the vagina, and activities such as gymnastics (doing 'the splits'), or horseback riding.[6] Remnants of the hymen are called carunculae myrtiformes.[9]

A glass or plastic rod of 6 mm diameter having a globe on one end with varying diameter from 10 to 25 mm, called a Glaister Keen rod, is used for close examination of the hymen or the degree of its rupture. In forensic medicine, it is recommended by health authorities that a physician who must swab near this area of a prepubescent girl avoid the hymen and swab the outer vulval vestibule instead.[12] 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.[2]

Anatomic variations

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

Normal variations of the hymen range from thin and stretchy to thick and somewhat rigid; or it may also be completely absent.[1][12] An imperforate hymen occurs in 1-2 out of 1,000 infants.[15][16] The only variation that may require medical intervention is the imperforate hymen, which either completely prevents the passage of menstrual fluid or slows it significantly. In either case, surgical intervention may be needed to allow menstrual fluid to pass or intercourse to take place at all.

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 fimbriated or erratically shaped.[13] 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]

Variations of the female reproductive tract can result from agenesis or hypoplasia, canalization defects, lateral fusion and failure of resorption, resulting in various complications.[14]

  • Imperforate:[17][18] 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.

Trauma

Historically, it was believed that first sexual intercourse was necessarily traumatic to the hymen and always resulted in the hymen being "broken" or torn, causing bleeding. However, research on women in Western populations has found that bleeding during first consensual intercourse does not always happen or is less common than not bleeding.[7][8][19] In one cross-cultural study, slightly more than half of all women self-reported bleeding during first intercourse, with significantly different levels of pain and bleeding reported depending on their region of origin.[20][19]

In several studies of adolescent female rape victims, where patients were examined at a hospital following sexual assault, half or fewer of virgin victims had any injury to the hymen.[21][22][23] Tears of the hymen occurred in less than a quarter of cases.[23] However, virgins were significantly more likely to have injuries to the hymen than non-virgins.[21][23]

In a study of adolescents who had previously had consensual sex, approximately half showed evidence of trauma to the hymen.[24][25] Trauma to the hymen may also occur in adult non-virgins following consensual sex, although it is rare.[26] Trauma to the hymen may heal without any visible sign of injury.[21][25][1] An observational study of adolescent sexual assault victims found that majority of wounds to the hymen healed without any visible sign of injury having occurred.[27]

Trauma to the hymen is hypothesized to occur as a result of various other behaviors, such as tampon or menstrual cup use, pelvic examinations with a speculum, masturbation, gymnastics, or horseback riding, although the true prevalence of trauma as a result of these activities is unclear.[6][28][29]

Cultural significance

The hymen is often attributed important cultural significance in certain communities because of its association with a woman's virginity.[6] In those cultures, an intact hymen is highly valued at marriage in the belief that this is a proof of virginity.[6][30][31] Some women undergo hymenorrhaphy to restore their hymen for this reason.[31]

In October 2018, the UN Human Rights, UN Women and the World Health Organization (WHO) stated that virginity testing must end as it is a painful, humiliating and traumatic practice, constituting violence against women.[32]

Womb fury

In the 16th and 17th centuries, medical researchers mistakenly saw the presence or absence of the hymen as founding evidence of physical diseases such as "womb-fury", i.e., (female) hysteria. If not cured, womb-fury would, according to doctors practicing at the time, result in death.[33][34]

Other animals

Due to similar reproductive system development, many mammals have hymens, including chimpanzees, elephants, manatees, whales, horses and llamas.[35][36]

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Heger, Astrid H., ed (2000) (in English). Evaluation of the Sexually Abused Child: A Medical Textbook and Photographic Atlas (2nd ed.). New York: Oxford University Press. pp. 61–65. ISBN 9780195074253. https://the-eye.eu/public/Books/Medical/texts/Evaluation%20of%20the%20Sexually%20Abused%20Child%202nd%20ed%20-%20A.%20Heger%2C%20et%20al.%2C%20%28Oxford%2C%202000%29%20WW.pdf. 
  2. ↑ 2.0 2.1 2.2 Perlman, Sally E.; Nakajyma, Steven T.; Hertweck, S. Paige (2004). Clinical protocols in pediatric and adolescent gynecology. Parthenon. p. 131. ISBN 978-1-84214-199-1. 
  3. ↑ 3.0 3.1 Blank, Hanne (2008). Virgin: The Untouched History. Bloomsbury USA. p. 35. ISBN 978-1-59691-011-9. https://books.google.com/books?id=_USgAwAAQBAJ. 
  4. ↑ 4.0 4.1 Lahoti, Sheela L.; McClain, Natalie; Girardet, Rebecca; McNeese, Margaret; Cheung, Kim (2001-03-01). "Evaluating the Child for Sexual Abuse" (in en). American Family Physician 63 (5). ISSN 0002-838X. http://www.aafp.org/afp/2001/0301/p883.html. 
  5. ↑ 5.0 5.1 Heger, Astrid H., ed (2000) (in English). Evaluation of the Sexually Abused Child: A Medical Textbook and Photographic Atlas (2nd ed.). New York: Oxford University Press. pp. 122. ISBN 9780195074253. https://the-eye.eu/public/Books/Medical/texts/Evaluation%20of%20the%20Sexually%20Abused%20Child%202nd%20ed%20-%20A.%20Heger%2C%20et%20al.%2C%20%28Oxford%2C%202000%29%20WW.pdf. 
  6. ↑ 6.0 6.1 6.2 6.3 6.4 "The Hymen". University of California, Santa Barbara. http://www.soc.ucsb.edu/sexinfo/article/hymen. Retrieved 2009-02-09. "The hymen oftentimes, though not always, rips or tears the first time a female engages in penetrative intercourse, which may cause some temporary bleeding and slight discomfort." 
  7. ↑ 7.0 7.1 Rogers, Deborah J; Stark, Margaret (1998-08-08). "The hymen is not necessarily torn after sexual intercourse". BMJ: British Medical Journal 317 (7155): 414. doi:10.1136/bmj.317.7155.414. ISSN 0959-8138. PMID 9694770. 
  8. ↑ 8.0 8.1 Emma Curtis, Camille San Lazaro (1999-02-27). "Appearance of the hymen in adolescents is not well documented" (in en). BMJ: British Medical Journal 318 (7183): 605. doi:10.1136/bmj.318.7183.605. PMID 10037658. "We agree with Rogers and Stark that so called rupture and bleeding of the hymen is not to be routinely expected after first sexual intercourse.". 
  9. ↑ 9.0 9.1 Knight, Bernard (1997). Simpson's Forensic Medicine (11th ed.). London: Arnold. p. 114. ISBN 978-0-7131-4452-9. 
  10. ↑ Hegazy, Abdelmonem; Al-Rukban, Mohammed (2012-01-01). "Hymen: Facts and conceptions" (in en). TheHealth 3 (4). ISSN 2219-8083. https://www.researchgate.net/publication/260578888. "Possible explanations for the lack of genital trauma include... acute injuries occur but heal completely.". 
  11. ↑ Healey, Andrew (2012). "Embryology of the female reproductive tract". Imaging of Gynecological Disorders in Infants and Children. Medical Radiology. Springer. pp. 21–30. doi:10.1007/978-3-540-85602-3. ISBN 978-3-540-85602-3. 
  12. ↑ 12.0 12.1 12.2 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.
  13. ↑ 13.0 13.1 Heger, Astrid; Emans, S. Jean; Muram, David (2000). Evaluation of the Sexually Abused Child: A Medical Textbook and Photographic Atlas (Second ed.). Oxford University Press. p. 116. ISBN 978-0-19-507425-3. 
  14. ↑ 14.0 14.1 "Imperforate Hymen". http://emedicine.medscape.com/article/269050-overview. 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." 
  15. ↑ Callahan, Tamara L.; Caughey, Aaron B. (2009) (in en). Blueprints Obstetrics and Gynecology. Lippincott Williams & Wilkins. ISBN 9780781782494. https://books.google.com/?id=H7Z-lD9cXBEC&pg=PA139&dq=vaginal+labial+fusion#v=onepage&q=vaginal%20labial%20fusion&f=false. 
  16. ↑ Lardenoije, Céline; Aardenburg, Robert; Mertens, Helen (2009-05-26). "Imperforate hymen: a cause of abdominal pain in female adolescents". BMJ Case Reports 2009: bcr0820080722. doi:10.1136/bcr.08.2008.0722. ISSN 1757-790X. PMID 21686660. 
  17. ↑ Steinberg, Avraham; Rosner, Fred (2003). Encyclopedia of Jewish Medical Ethics. ISBN 978-1-58330-592-8. https://books.google.com/?id=aaklGZAID08C&pg=PA1115&dq=hymen. "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 ..." 
  18. ↑ DeCherney, Alan H.; Pernoll, Martin L.; Nathan, Lauren (2002). Current Obstetric & Gynecologic Diagnosis & Treatment. McGraw-Hill Professional. p. 602. ISBN 978-0-8385-1401-6. https://books.google.com/?id=9xD0inFiEIAC&printsec=frontcover#PPA602,M1. "Imperforate hymen represents a persistent portion of the urogenital membrane ... It is one of the most common obstructive lesions of the female genital tract. ..." 
  19. ↑ 19.0 19.1 Loeber, Olga (2008). "Over het zwaard en de schede; bloedverlies en pijn bij de eerste coïtus Een onderzoek bij vrouwen uit diverse culturen" (in nl-nl). Tijdschrift voor Seksuologie 32: pp. 129–137. https://www.tijdschriftvoorseksuologie.nl/media/k2/attachments/loeberZtvsZ32-3.pdf. 
  20. ↑ Amy, Jean-Jacques (January 2008). "Certificates of virginity and reconstruction of the hymen" (in en). The European Journal of Contraception & Reproductive Health Care 13 (2): 111–113. doi:10.1080/13625180802106045. ISSN 1362-5187. PMID 18465471. 
  21. ↑ 21.0 21.1 21.2 White, C., & McLean, I. (2006-05-01). "Adolescent complainants of sexual assault; injury patterns in virgin and non-virgin groups" (in en). Journal of Clinical Forensic Medicine 13 (4): 172–180. doi:10.1016/j.jcfm.2006.02.006. ISSN 1353-1131. PMID 16564196. "Hymen injury was noted in 40 (50.6%) participants of the virgin group, but only 11 (12.4%) of the non-virgin group". 
  22. ↑ Adams, Joyce A.; Girardin, Barbara; Faugno, Diana (May 2000). "Signs of genital trauma in adolescent rape victims examined acutely" (in English). Journal of Pediatric and Adolescent Gynecology 13 (2): 88. doi:10.1016/S1083-3188(00)00015-2. ISSN 1083-3188. https://www.jpagonline.org/article/S1083-3188(00)00015-2/abstract. 
  23. ↑ 23.0 23.1 23.2 Adams, Joyce A.; Girardin, Barbara; Faugno, Diana (2001-11-01). "Adolescent Sexual Assault: Documentation of Acute Injuries Using Photo-colposcopy" (in en). Journal of Pediatric and Adolescent Gynecology 14 (4): 175–180. doi:10.1016/S1083-3188(01)00126-7. ISSN 1083-3188. "The incidence of hymenal tears in self-described virgins was higher than in nonvirgins (19% vs. 3%, P .008);". 
  24. ↑ Adams, Joyce A.; Botash, Ann S.; Kellogg, Nancy (March 2004). "Differences in hymenal morphology between adolescent girls with and without a history of consensual sexual intercourse". Archives of Pediatrics & Adolescent Medicine 158 (3): 280–285. doi:10.1001/archpedi.158.3.280. ISSN 1072-4710. PMID 14993089. "Subjects who admitted having past intercourse still had non disrupted, intact hymens in 52% of cases.". 
  25. ↑ 25.0 25.1 "New York Times Is Wrong about Hymens--But They Are Not Alone" (in en-GB). https://www.psychologytoday.com/gb/blog/you-it/200806/new-york-times-is-wrong-about-hymens-they-are-not-alone. 
  26. ↑ Slaughter, Laura; Brown, Carl R.V.; Crowley, Sharon; Peck, Roxy (March 1997). "Patterns of genital injury in female sexual assault victims". American Journal of Obstetrics and Gynecology 176 (3): 609–616. doi:10.1016/s0002-9378(97)70556-8. ISSN 0002-9378. PMID 9077615. 
  27. ↑ Reading, Richard (2007-12-12). "Healing of hymenal injuries in prepubertal and adolescent girls: a descriptive study" (in en). Child: Care, Health and Development 34 (1): 137–138. doi:10.1111/j.1365-2214.2007.00818_7.x. ISSN 0305-1862. "Of the girls who sustained ‘superficial’, ‘intermediate,’ or ‘deep’ lacerations, 15 of 18 prepubertal girls had smooth and continuous appearing hymenal rims, whereas 24 of 41 adolescents' hymens had a normal, ‘scalloped’ appearance and 30 of 34 had no disruption of continuity on healing. The final ‘width’ of a hymenal rim was dependent on the initial depth of the laceration. No scar tissue formation was observed in either group of girls.". 
  28. ↑ Goodyear-Smith, Felicity A.; Laidlaw, Tannis M. (1998-06-08). "Can tampon use cause hymen changes in girls who have not had sexual intercourse? A review of the literature" (in en). Forensic Science International 94 (1–2): 147–153. doi:10.1016/S0379-0738(98)00053-X. ISSN 0379-0738. 
  29. ↑ Emans, S.Jean; Woods, Elizabeth R.; Allred, Elizabeth N.; Grace, Estherann (1994-07-01). "Hymenal findings in adolescent women: Impact of tampon use and consensual sexual activity" (in en). The Journal of Pediatrics 125 (1): 153–160. doi:10.1016/S0022-3476(94)70144-X. ISSN 0022-3476. "Contrary to the popular belief that transections of the hymen are associated with gymnastics, horseback riding, and other vigorous sports, we found no relation between sports or gymnastics and hymenal changes. There was also no relation to prior gynecologic examination.". 
  30. ↑ "Muslim women in France regain virginity in clinics". Reuters. April 30, 2007. https://www.reuters.com/article/2007/04/30/us-muslimwomen-europe-virginity-idUSL2532025120070430?pageNumber=2&sp=true. "'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'." 
  31. ↑ 31.0 31.1 "In Europe, Debate Over Islam and Virginity". The New York Times. June 11, 2008. https://www.nytimes.com/2008/06/11/world/europe/11virgin.html?_r=1&scp=1&sq=hymen&st=nyt&oref=slogin. 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.'" 
  32. ↑ "United Nations agencies call for ban on virginity testing". World Health Organization. 17 October 2018. http://www.who.int/news-room/detail/17-10-2018-united-nations-agencies-call-for-ban-on-virginity-testing. 
  33. ↑ Berrios, GE; Rivière, L (2006). "Madness from the womb". History of Psychiatry 17: 223–35. doi:10.1177/0957154x06065699. 
  34. ↑ 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
  35. ↑ Blank, Hanne (2007). Virgin: The Untouched History. Bloomsbury Publishing. p. 23. ISBN 978-1-59691-010-2. https://books.google.com/?id=shq1AAAAIAAJ&dq=Virgin%3A+The+Untouched+History&q=toothed+whales. Retrieved 2013-11-09. 
  36. ↑ Blackledge, Catherine (2004). The Story of V. Rutgers University Press. ISBN 978-0-8135-3455-8. https://books.google.com/?id=f2d-11Y_u3cC&pg=PP250&dq=guinea+pig+hymen. "Hymens, or vaginal closure membranes or vaginal constrictions, as they are often referred to, are found in a number of mammals, including llamas, ..." 

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