Màng trinh

Gesch_embryonal.png Màng trinh là một màng mỏng nằm trong âm đạo, cách cửa âm đạo khoảng 1 cm. Màng sẽ bị rách ở lần giao hợp đầu tiên hoặc do chơi thể thao, chạy nhảy, đi xe đạp ... Khi màng trinh bị rách cơ thể chảy một vài giọt máu, hoặc chỉ có chút chất tiết hơi hồng. Một số bạn gái khi sinh ra đã không có màng này hoặc nó đàn hồi đến mức tiếp tục tồn tại cho đến lần sinh con đầu tiên.

Màng trinh thật ra là một phần dư sót lại trong thời kỳ thai nhi phát triển. Do đó, có nhiều bé gái khi sinh ra đã không có màng trinh, trong khi ở một số phụ nữ màng trinh dầy và che kín âm đạo gây trở ngại khi giao hợp và có triệu chứng không có kinh. Vì văn hóa xưa nay coi trọng vấn đề giữ trinh tiết nên màng trinh được nhiều chú ý Hình:Hymen.png|Mô tả các cơ quan sinh dục nữ cùng màng trinh Hình:Gp-168-hymen afwijkingen.jpg|Phác thảo cấu tạo

The hymen (or maidenhead) is a ring of tissue around the vaginal opening. The term comes from a Greek word meaning "membrane". Although many people believe that the hymen completely occludes the vaginal opening in human females, this is quite rare. The hymen has great symbolic significance as an indicator of a woman's virginity. Lately, the very concept of a hymen has been criticized and even its existence questioned by researchers who consider it to be based more on cultural perceptions and sexual stereotypes than physiological facts.

Hymens in animals

Many mammals have hymens, including (but not limited to) llamas, guinea pigs, bush babies, manatees, moles, toothed whales, chimpanzees, elephants, rats, lemurs and seals.

Historical significance

Because of the belief that first vaginal penetration would usually tear this membrane and cause bleeding, its "intactness" has been considered a guarantor of virginity in societies that place a high value on female chastity before marriage. However, the hymen is a poor indicator of whether a woman has actually engaged in sexual intercourse because a normal hymen does not completely block the vaginal opening. The normal hymen is never actually "intact" since there is always an opening in it. Furthermore, there is not always bleeding at first vaginal penetration. The blood that is sometimes, but not always, observed after first penetration can be due to tearing of the hymen, but it can also be from injury to nearby tissues. Post-injury, injuries to the hymen and surrounding tissues often quickly heal, leaving the hymenal tissue looking as if there had been no injury at all^*

A tear to the hymen, medically referred to as a "transection," can be seen in a small percentage of women or girls after first penetration. A transection is caused by penetrating trauma. Masturbation and tampon insertion are not forceful enough to cause penetrating trauma to the hymen (Bays in Reece, 2001: 297). Straddle injuries due to sports like bicycling, horseback riding, or gymnastics also do not cause transections. Straddle injuries generally cause injuries over the pubic bone, tailbone, or to either side of the vaginal opening. Since straddle injuries are not penetrating injuries, they do not cause transections of the hymen (Bays in Reece, 2001: 295-6).

Also, there are surgeons who claim to be able to surgically restore a woman's hymen in order to feign not having engaged in intercourse.

Therefore, for all of the above reasons, the appearance of the hymen is not a reliable indicator of virginity or chastity.

Reference: "Conditions Mistaken for Child Sexual Abuse," Bays, J in Child Abuse: Medical Diagnosis and Management, Reece RM and Ludwig S, eds. Lippincott Williams & Wilkins, 2001.

Types

The size and shape of this opening (or openings) vary greatly from person to person. Rarely, women are born with no hymen at all, while (equally rarely) others have a closed or imperforate hymen. These women may require a gynecologist to perform a medical procedure called a hymenotomy to allow menstrual products to escape. Still other women have unusually thick hymens that may require a hymenotomy to prevent pain for the woman during sex. In a woman or girl past puberty, the general structure of the hymen can be compared to a hair scrunchie in that it is elastic and stretches open easily (for a picture of a hair scrunchie go to http://www.bishopstontrading.co.uk/catalogue/bags/xmas05scrunchieL.jpg). Some other common forms of hymen are:

Annular – in which the hymen forms a ring around the vaginal opening.
Septate – in which the hymen has one or more bands extending across the opening.
Cribriform – in which the hymen stretches completely across the vaginal opening, but is perforated with several holes.
Parous Introitus – which refers to the vaginal opening which has had a baby pass through it and consequently has nothing left of its hymen but a fleshy irregular outline decorating its perimeter. It is important to note that some women have completely normal hymens (all tissue still there and not injured) even after giving birth.

Development

During the early stages of fetal development there is no opening into the vagina at all. The thin layer of tissue that covers the vagina at this time usually divides to a certain extent prior to birth, forming the hymen. In a very small percentage of female births, this tissue has divided completely, and the baby is born without a hymen.

Cultural construction

In late 2005 Monica Christiansson, former maternity ward nurse and Carola Eriksson, a PhD student at Umeå University announced that according to studies of medical literature and practical experience, the hymen should be considered a social and cultural myth, based on deeply rooted stereotypes of womens' roles in sexual relations with men. Christiansson and Eriksson support their claims by pointing out that there are no accurate medical descriptions of what a hymen actually consists of. Statistics presented by the two show that fewer than 30% of all women who have gone through puberty and have consensual intercourse bleed the first time. Christiansson has expressed an opinion that the use of the term "hymen" should be discontinued and that it should be considered an integral part of the vaginal opening.

The slang term "cherry" is also commonly used as a reference to a woman's hymen. Specifically, the phrase "popping the/her cherry" indicates a loss of a woman's virginity. The cherry may have been chosen because its bright red color and juice is similar to blood, and many women bleed when having intercourse for the first time.

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Liên kết ngoài

Hymen gallery - Illustrations of hymen types (no explicit photos)
Pink Parts - "Walk through" of female sexual anatomy by noted sex activist and educator Heather Corinna (no explicit photos)
Magical Cups and Bloody Brides the historical context of virginity in a frank and easy-to-understand manner.
20 Questions About Virginity - Interview with Hanne Blank, author of an upcoming book on virginity. Discusses relationship between hymen and concept of virginity.
Nerikes Allehanda's article on Christiansson's and Erikisson's research

Female reproductive system | Phụ khoa