Vagina
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Vaginal health is an important part of women's overall health. Vaginal problems can affect fertility, desire for sex and ability to reach orgasm. Ongoing vaginal health issues can also cause stress or relationship problems and affect self-confidence. Know the signs and symptoms of vaginal problems and what you can do to protect your vaginal health.
The vagina is a muscular canal that extends from the vulva to the neck of the uterus (cervix). The vagina is where the lining of the uterus is shed during menstruation, where penetration can occur during sex and where a baby descends during childbirth.
The vagina is a closed muscular canal that extends from the outside of the female genital area (vulva) to the neck of the uterus (cervix). Various factors can affect the health of the vagina, including:
You might not need to see your health care provider every time you have vaginal irritation and discharge, particularly if you've been diagnosed with a vaginal yeast infection in the past and you're having similar signs and symptoms. However, if your symptoms don't go away after you use a medication that you get at your drugstore, consult your provider.
While not all vaginal problems can be prevented, regular checkups can help ensure that problems affecting the vagina are diagnosed as soon as possible. Don't let embarrassment prevent you from talking to your health care provider about concerns you have about vaginal health.
In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen. At the deep end, the cervix (neck of the uterus) bulges into the vagina. The vagina allows for sexual intercourse and birth. It also channels menstrual flow, which occurs in humans and closely related primates as part of the menstrual cycle.
Although research on the vagina is especially lacking for different animals, its location, structure and size are documented as varying among species. Female mammals usually have two external openings in the vulva; these are the urethral opening for the urinary tract and the vaginal opening for the genital tract. This is different from male mammals, who usually have a single urethral opening for both urination and reproduction. The vaginal opening is much larger than the nearby urethral opening, and both are protected by the labia in humans. In amphibians, birds, reptiles and monotremes, the cloaca is the single external opening for the gastrointestinal, urinary, and reproductive tracts.
To accommodate smoother penetration of the vagina during sexual intercourse or other sexual activity, vaginal moisture increases during sexual arousal in human females and other female mammals. This increase in moisture provides vaginal lubrication, which reduces friction. The texture of the vaginal walls creates friction for the penis during sexual intercourse and stimulates it toward ejaculation, enabling fertilization. Along with pleasure and bonding, women's sexual behavior with others (which can include heterosexual or lesbian sexual activity) can result in sexually transmitted infections (STIs), the risk of which can be reduced by recommended safe sex practices. Other health issues may also affect the human vagina.
The vagina and vulva have evoked strong reactions in societies throughout history, including negative perceptions and language, cultural taboos, and their use as symbols for female sexuality, spirituality, or regeneration of life. In common speech, the word vagina is often used to refer to the vulva or to the female genitals in general. By its dictionary and anatomical definitions, however, vagina refers exclusively to the specific internal structure, and understanding the distinction can improve knowledge of the female genitalia and aid in healthcare communication.
The term vagina is from Latin meaning \"sheath\" or \"scabbard\"; the plural of vagina is either vaginae, or vaginas.[1] The vagina may also be referred to as the birth canal in the context of pregnancy and childbirth.[2][3] Although by its dictionary and anatomical definitions, the term vagina refers exclusively to the specific internal structure, it is colloquially used to refer to the vulva or to both the vagina and vulva.[4][5]
Using the term vagina to mean \"vulva\" can pose medical or legal confusion; for example, a person's interpretation of its location might not match another's interpretation of the location.[4][6] Medically, one description of the vagina is that it is the canal between the hymen (or remnants of the hymen) and the cervix, while a legal description is that it begins at the vulva (between the labia).[4] It may be that the incorrect use of the term vagina is due to not as much thought going into the anatomy of the female genitals as has gone into the study of male genitals, and that this has contributed to an absence of correct vocabulary for the external female genitalia among both the general public and health professionals. Because a better understanding of female genitalia can help combat sexual and psychological harm with regard to female development, researchers endorse correct terminology for the vulva.[6][7][8]
The human vagina is an elastic, muscular canal that extends from the vulva to the cervix.[9][10] The opening of the vagina lies in the urogenital triangle. The urogenital triangle is the front triangle of the perineum and also consists of the urethral opening and associated parts of the external genitalia.[11] The vaginal canal travels upwards and backwards, between the urethra at the front, and the rectum at the back. Near the upper vagina, the cervix protrudes into the vagina on its front surface at approximately a 90 degree angle.[12] The vaginal and urethral openings are protected by the labia.[13]
When not sexually aroused, the vagina is a collapsed tube, with the front and back walls placed together. The lateral walls, especially their middle area, are relatively more rigid. Because of this, the collapsed vagina has an H-shaped cross section.[10][14] Behind, the upper vagina is separated from the rectum by the recto-uterine pouch, the middle vagina by loose connective tissue, and the lower vagina by the perineal body.[15] Where the vaginal lumen surrounds the cervix of the uterus, it is divided into four continuous regions (vaginal fornices); these are the anterior, posterior, right lateral, and left lateral fornices.[9][10] The posterior fornix is deeper than the anterior fornix.[10]
Supporting the vagina are its upper, middle, and lower third muscles and ligaments. The upper third are the levator ani muscles, and the transcervical, pubocervical, and sacrocervical ligaments.[9][16] It is supported by the upper portions of the cardinal ligaments and the parametrium.[17] The middle third of the vagina involves the urogenital diaphragm.[9] It is supported by the levator ani muscles and the lower portion of the cardinal ligaments.[17] The lower third is supported by the perineal body,[9][18] or the urogenital and pelvic diaphragms.[19] The lower third may also be described as being supported by the perineal body and the pubovaginal part of the levator ani muscle.[16]
The vaginal opening is at the posterior end of the vulval vestibule, behind the urethral opening. The opening to the vagina is normally obscured by the labia minora (vaginal lips), but may be exposed after vaginal delivery.[10]
The hymen is a thin layer of mucosal tissue that surrounds or partially covers the vaginal opening.[10] The effects of intercourse and childbirth on the hymen are variable. Where it is broken, it may completely disappear or remnants known as carunculae myrtiformes may persist. Otherwise, being very elastic, it may return to its normal position.[20] Additionally, the hymen may be lacerated by disease, injury, medical examination, masturbation or physical exercise. For these reasons, virginity cannot be definitively determined by examining the hymen.[20][21]
The length of the vagina varies among women of child-bearing age. Because of the presence of the cervix in the front wall of the vagina, there is a difference in length between the front wall, approximately 7.5 cm (2.5 to 3 in) long, and the back wall, approximately 9 cm (3.5 in) long.[10][22] During sexual arousal, the vagina expands both in length and width. If a woman stands upright, the vaginal canal points in an upward-backward direction and forms an angle of approximately 45 degrees with the uterus.[10][18] The vaginal opening and hymen also vary in size; in children, although the hymen commonly appears crescent-shaped, many shapes are possible.[10][23]
The vaginal plate is the precursor to the vagina.[24] During development, the vaginal plate begins to grow where the fused ends of the paramesonephric ducts (Müllerian ducts) enter the back wall of the urogenital sinus as the sinus tubercle. As the plate grows, it significantly separates the cervix and the urogenital sinus; eventually, the central cells of the plate break down to form the vaginal lumen.[24] This usually occurs by the twenty to twenty-fourth week of development. If the lumen does not form, or is incomplete, membranes known as vaginal septae can form across or around the tract, causing obstruction of the outflow tract later in life.[24]
During sexual differentiation, without testosterone, the urogenital sinus persists as the vestibule of the vagina. The two urogenital folds of the genital tubercle form the labia minora, and the labioscrotal swellings enlarge to form the labia majora.[25][26]
There are conflicting views on the embryologic origin of the vagina. The majority view is Koff's 1933 description, which posits that the upper two-thirds of the vagina originate from the caudal part of the Müllerian duct, while the lower part of the vagina develops from the urogenital sinus.[27][28] Other views are Bulmer's 1957's description that the vaginal epithelium derives solely from the urogenital sinus epithelium,[29] and Witschi's 1970 research, which reexamined Koff's description and concluded that the sinovaginal bulbs are the same as the lower portions of the Wolffian ducts.[28][30] Witschi's view is supported by research by Acién et al., Bok and Drews.[28][30] Robboy et al. reviewed Koff and Bulmer's theories, and support Bulmer's description in light of their own research.[29] The debates stem from the complexity of the interrelated tissues and the absence of an animal model that matches human vaginal development.[29][31] Because of this, study of human vaginal development is ongoing and may help resolve the conflicting data.[28] 59ce067264