92-501: In mammals and other animals, the vagina ( pl. : vaginas or vaginae ) is the elastic, muscular reproductive organ of the female genital tract . In humans, it extends from the vulval vestibule to the cervix (neck of the uterus ). The vaginal introitus is normally partly covered by a thin layer of mucosal tissue called the hymen . The vagina allows for copulation and birth . It also channels menstrual flow , which occurs in humans and closely related primates as part of
184-450: A caesarean section (C-section) may be performed. The vaginal mucosa has an abnormal accumulation of fluid ( edematous ) and is thin, with few rugae, a little after birth. The mucosa thickens and rugae return in approximately three weeks once the ovaries regain usual function and estrogen flow is restored. The vaginal opening gapes and is relaxed, until it returns to its approximate pre-pregnant state six to eight weeks after delivery, known as
276-616: A urethral opening in the glans penis . 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
368-416: 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. The human vagina is an elastic, muscular canal that extends from the vulva to the cervix. The opening of the vagina lies in the urogenital triangle . The urogenital triangle is the front triangle of the perineum and also consists of
460-465: A broad attachment to the pubic arch and extensive supporting tissue to the labia. Research indicates that it forms a tissue cluster with the vagina. This tissue is perhaps more extensive in some women than in others, which may contribute to orgasms experienced vaginally. During sexual arousal, and particularly the stimulation of the clitoris, the walls of the vagina lubricate. This begins after ten to thirty seconds of sexual arousal, and increases in amount
552-412: A legal description is that it begins at the vulva (between the labia ). 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
644-440: A network of smaller veins, the vaginal venous plexus , on the sides of the vagina, connecting with similar venous plexuses of the uterus , bladder , and rectum . These ultimately drain into the internal iliac veins . The nerve supply of the upper vagina is provided by the sympathetic and parasympathetic areas of the pelvic plexus . The lower vagina is supplied by the pudendal nerve . Vaginal secretions are primarily from
736-470: A primary means of sexual pleasure. In contrast, lesbians and other women who have sex with women commonly engage in fingering as a main form of sexual activity . Some women and couples use sex toys , such as a vibrator or dildo , for vaginal pleasure. Most women require direct stimulation of the clitoris to orgasm. The clitoris plays a part in vaginal stimulation. It is a sex organ of multiplanar structure containing an abundance of nerve endings, with
828-446: A result of antibiotic use) or another form of vaginitis. While vaginitis is an inflammation of the vagina, and is attributed to infection, hormonal issues, or irritants, vaginismus is an involuntary tightening of the vagina muscles during vaginal penetration that is caused by a conditioned reflex or disease. Vaginal discharge due to yeast infection is usually thick, creamy in color and odorless, while discharge due to bacterial vaginosis
920-448: Is acidic , with a pH normally ranging between 3.8 and 4.5. The low pH prohibits growth of many strains of pathogenic microbes. The acidic balance of the vagina may also be affected by semen, pregnancy, menstruation, diabetes or other illness, birth control pills , certain antibiotics , poor diet, and stress. Any of these changes to the acidic balance of the vagina may contribute to yeast infection. An elevated pH (greater than 4.5) of
1012-407: Is colloquially used to refer to the vulva or to both the vagina and vulva. 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. Medically, one description of the vagina is that it is the canal between the hymen (or remnants of the hymen) and the cervix , while
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#17327839710211104-671: Is a route of administration where the medication is inserted into the vagina as a creme or tablet. Pharmacologically , this has the potential advantage of promoting therapeutic effects primarily in the vagina or nearby structures (such as the vaginal portion of cervix ) with limited systemic adverse effects compared to other routes of administration. Medications used to ripen the cervix and induce labor are commonly administered via this route, as are estrogens, contraceptive agents, propranolol , and antifungals . Vaginal rings can also be used to deliver medication, including birth control in contraceptive vaginal rings . These are inserted into
1196-427: 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. 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 . Where the vaginal lumen surrounds
1288-426: Is a high degree of variability in timing, girls who are approximately seven to twelve years of age will continue to have labial development as the hymen thickens and the vagina elongates to approximately 8 cm. The vaginal mucosa thickens and the vaginal pH becomes acidic again. Girls may also experience a thin, white vaginal discharge called leukorrhea . The vaginal microbiota of adolescent girls aged 13 to 18 years
1380-479: Is composed of smooth muscle fibers, with an outer layer of longitudinal muscle, an inner layer of circular muscle, and oblique muscle fibers between. The outer layer, the adventitia, is a thin dense layer of connective tissue and it blends with loose connective tissue containing blood vessels, lymphatic vessels and nerve fibers that are between pelvic organs. The vaginal mucosa is absent of glands. It forms folds (transverse ridges or rugae ), which are more prominent in
1472-461: Is gray-white in color, and discharge due to trichomoniasis is usually a gray color, thin in consistency, and has a fishy odor. Discharge in 25% of the trichomoniasis cases is yellow-green. HIV/AIDS , human papillomavirus (HPV), genital herpes and trichomoniasis are some STIs that may affect the vagina, and health sources recommend safe sex (or barrier method) practices to prevent the transmission of these and other STIs. Safe sex commonly involves
1564-414: Is hypothesized to be an extension of the clitoris and therefore the reason for orgasms experienced vaginally. The vagina is the birth canal for the delivery of a baby. When labor nears, several signs may occur, including vaginal discharge and the rupture of membranes (water breaking). The latter results in a gush or small stream of amniotic fluid from the vagina. Water breaking most commonly happens at
1656-460: Is normally obscured by the labia minora (inner lips), but may be exposed after vaginal delivery . The hymen is a thin layer of mucosal tissue that surrounds or partially covers the vaginal opening. The effects of intercourse and childbirth on the hymen vary. 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. Additionally,
1748-572: Is primarily driven by human poaching and habitat destruction , primarily deforestation . Over 70% of mammal species are in the orders Rodentia , Chiroptera , and Eulipotyphla . Mammal classification has been through several revisions since Carl Linnaeus initially defined the class, and at present , no classification system is universally accepted. McKenna & Bell (1997) and Wilson & Reeder (2005) provide useful recent compendiums. Simpson (1945) provides systematics of mammal origins and relationships that had been taught universally until
1840-443: Is red in color before puberty. When puberty begins, the mucosa thickens and again becomes stratified squamous epithelium with glycogen containing cells, under the influence of the girl's rising estrogen levels. Finally, the epithelium thins out from menopause onward and eventually ceases to contain glycogen, because of the lack of estrogen. Flattened squamous cells are more resistant to both abrasion and infection. The permeability of
1932-423: Is similar to women of reproductive age, who have an average vaginal pH of 3.8–4.5, but research is not as clear on whether this is the same for premenarcheal or perimenarcheal girls. The vaginal pH during menopause is 6.5–7.0 (without hormone replacement therapy ), or 4.5–5.0 with hormone replacement therapy. Mammal A mammal (from Latin mamma 'breast') is a vertebrate animal of
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#17327839710212024-444: Is supported by research by Acién et al., Bok and Drews. Robboy et al. reviewed Koff and Bulmer's theories, and support Bulmer's description in light of their own research. The debates stem from the complexity of the interrelated tissues and the absence of an animal model that matches human vaginal development. Because of this, study of human vaginal development is ongoing and may help resolve the conflicting data. The vaginal wall from
2116-399: Is supported by the upper portions of the cardinal ligaments and the parametrium . The middle third of the vagina involves the urogenital diaphragm . It is supported by the levator ani muscles and the lower portion of the cardinal ligaments. The lower third is supported by the perineal body, or the urogenital and pelvic diaphragms . The lower third may also be described as being supported by
2208-426: Is the viviparous placental mammals , so named for the temporary organ ( placenta ) used by offspring to draw nutrition from the mother during gestation . Most mammals are intelligent , with some possessing large brains, self-awareness , and tool use . Mammals can communicate and vocalize in several ways, including the production of ultrasound , scent marking , alarm signals , singing , echolocation ; and, in
2300-411: Is the anterior part of the perineum . In female mammals , it contains the vulva , while in male mammals, it contains the penis and scrotum . The urogenital triangle is the area bound by a triangle with one vertex at the pubic symphysis and the two other vertices at the iliac tuberosities of the pelvic bone . As might be expected, the contents of the urogenital triangle differ greatly between
2392-415: Is the precursor to the vagina. 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 . This usually occurs by
2484-440: Is unclear on whether treating cervical cancer with radiation therapy increases the risk of vaginal cancer. Age and hormone levels significantly correlate with the pH of the vagina. Estrogen, glycogen and lactobacilli impact these levels. At birth, the vagina is acidic with a pH of approximately 4.5, and ceases to be acidic by three to six weeks of age, becoming alkaline. Average vaginal pH is 7.0 in pre-pubertal girls. Although there
2576-470: Is used to treat endometrial , vaginal and cervical cancer. An applicator is inserted into the vagina to allow the administration of radiation as close to the site of the cancer as possible. Survival rates increase with VBT when compared to external beam radiation therapy. By using the vagina to place the emitter as close to the cancerous growth as possible, the systemic effects of radiation therapy are reduced and cure rates for vaginal cancer are higher. Research
2668-473: The Cretaceous . The relationships between these three lineages is contentious, and all three possible hypotheses have been proposed with respect to which group is basal . These hypotheses are Atlantogenata (basal Boreoeutheria), Epitheria (basal Xenarthra) and Exafroplacentalia (basal Afrotheria). Boreoeutheria in turn contains two major lineages— Euarchontoglires and Laurasiatheria . Estimates for
2760-564: The International Union for Conservation of Nature (IUCN) completed a five-year Global Mammal Assessment for its IUCN Red List , which counted 5,488 species. According to research published in the Journal of Mammalogy in 2018, the number of recognized mammal species is 6,495, including 96 recently extinct. The word " mammal " is modern, from the scientific name Mammalia coined by Carl Linnaeus in 1758, derived from
2852-556: The Latin mamma ("teat, pap"). In an influential 1988 paper, Timothy Rowe defined Mammalia phylogenetically as the crown group of mammals, the clade consisting of the most recent common ancestor of living monotremes ( echidnas and platypuses ) and therian mammals ( marsupials and placentals ) and all descendants of that ancestor. Since this ancestor lived in the Jurassic period, Rowe's definition excludes all animals from
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2944-570: The Skene's glands , a female homologue of the prostate , rather than any particular spot on the vaginal wall; other researchers consider the connection between the Skene's glands and the G-spot area to be weak. The G-spot's existence (and existence as a distinct structure) is still under dispute because reports of its location can vary from woman to woman, it appears to be nonexistent in some women, and it
3036-606: The biological classification scheme used, are the primates : apes , monkeys , and lemurs ; the Cetartiodactyla : whales and even-toed ungulates ; and the Carnivora which includes cats , dogs , weasels , bears , seals , and allies. According to Mammal Species of the World , 5,416 species were identified in 2006. These were grouped into 1,229 genera , 153 families and 29 orders. In 2008,
3128-647: The class Mammalia ( / m ə ˈ m eɪ l i . ə / ). Mammals are characterized by the presence of milk -producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair , and three middle ear bones . These characteristics distinguish them from reptiles and birds , from which their ancestors diverged in the Carboniferous Period over 300 million years ago. Around 6,400 extant species of mammals have been described and divided into 27 orders . The largest orders of mammals, by number of species , are
3220-406: The dominant terrestrial animal group from 66 million years ago to the present. The basic mammalian body type is quadrupedal , with most mammals using four limbs for terrestrial locomotion ; but in some, the limbs are adapted for life at sea , in the air , in trees or underground . The bipeds have adapted to move using only the two lower limbs, while the rear limbs of cetaceans and
3312-482: The inner lining of the uterus through the vagina. The vaginal mucous membrane varies in thickness and composition during the menstrual cycle , which is the regular, natural change that occurs in the female reproductive system (specifically the uterus and ovaries ) that makes pregnancy possible. Different hygiene products such as tampons , menstrual cups , and sanitary napkins are available to absorb or capture menstrual blood. The Bartholin's glands, located near
3404-413: 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 placental 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 placental mammals, which have
3496-424: The postpartum period ; however, the vagina will continue to be larger in size than it was previously. After giving birth, there is a phase of vaginal discharge called lochia that can vary significantly in the amount of loss and its duration but can go on for up to six weeks. The vaginal flora is a complex ecosystem that changes throughout life, from birth to menopause. The vaginal microbiota resides in and on
3588-428: The rodents , bats , and Eulipotyphla (including hedgehogs , moles and shrews ). The next three are the primates (including humans , monkeys and lemurs ), the even-toed ungulates (including pigs , camels , and whales ), and the Carnivora (including cats , dogs , and seals ). Mammals are the only living members of Synapsida ; this clade , together with Sauropsida (reptiles and birds), constitutes
3680-439: The sea cows are mere internal vestiges . Mammals range in size from the 30–40 millimetres (1.2–1.6 in) bumblebee bat to the 30 metres (98 ft) blue whale —possibly the largest animal to have ever lived. Maximum lifespan varies from two years for the shrew to 211 years for the bowhead whale . All modern mammals give birth to live young, except the five species of monotremes , which lay eggs. The most species-rich group
3772-508: The uterus , cervix, and vaginal epithelium in addition to minuscule vaginal lubrication from the Bartholin's glands upon sexual arousal. It takes little vaginal secretion to make the vagina moist; secretions may increase during sexual arousal, the middle of or a little prior to menstruation , or during pregnancy . Menstruation (also known as a "period" or "monthly") is the regular discharge of blood and mucosal tissue (known as menses) from
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3864-438: The back wall, approximately 9 cm (3.5 in) long. 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. The vaginal opening and hymen also vary in size; in children, although the hymen commonly appears crescent -shaped, many shapes are possible. The vaginal plate
3956-420: The beginning of labor. It happens before labor if there is a premature rupture of membranes , which occurs in 10% of cases. Among women giving birth for the first time, Braxton Hicks contractions are mistaken for actual contractions , but they are instead a way for the body to prepare for true labor. They do not signal the beginning of labor, but they are usually very strong in the days leading up to labor. As
4048-517: The body prepares for childbirth, the cervix softens, thins , moves forward to face the front, and begins to open. This allows the fetus to settle into the pelvis, a process known as lightening. As the fetus settles into the pelvis, pain from the sciatic nerves , increased vaginal discharge, and increased urinary frequency can occur. While lightening is likelier to happen after labor has begun for women who have given birth before, it may happen ten to fourteen days before labor in women experiencing labor for
4140-492: The case of humans, complex language . Mammals can organize themselves into fission–fusion societies , harems , and hierarchies —but can also be solitary and territorial . Most mammals are polygynous , but some can be monogamous or polyandrous . Domestication of many types of mammals by humans played a major role in the Neolithic Revolution , and resulted in farming replacing hunting and gathering as
4232-527: The caudal part of the Müllerian duct, while the lower part of the vagina develops from the urogenital sinus. Other views are Bulmer's 1957 description that the vaginal epithelium derives solely from the urogenital sinus epithelium, 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 . Witschi's view
4324-484: The cells begin to lose their mitochondria and other organelles . The cells retain a usually high level of glycogen compared to other epithelial tissue in the body. Under the influence of maternal estrogen, the vagina of a newborn is lined by thick stratified squamous epithelium (or mucosa) for two to four weeks after birth. Between then to puberty , the epithelium remains thin with only a few layers of cuboidal cells without glycogen. The epithelium also has few rugae and
4416-428: 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. The posterior fornix is deeper than the anterior fornix. 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. It
4508-412: The child, and is without significant complications. Vaginal infections or diseases include yeast infection , vaginitis , sexually transmitted infections (STIs) and cancer . Lactobacillus gasseri and other Lactobacillus species in the vaginal flora provide some protection from infections by their secretion of bacteriocins and hydrogen peroxide . The healthy vagina of a woman of child-bearing age
4600-812: The clade originating with the last common ancestor of Sinoconodon and living mammals. The earliest-known synapsid satisfying Kemp's definitions is Tikitherium , dated 225 Ma , so the appearance of mammals in this broader sense can be given this Late Triassic date. However, this animal may have actually evolved during the Neogene. As of the early 21st century, molecular studies based on DNA analysis have suggested new relationships among mammal families. Most of these findings have been independently validated by retrotransposon presence/absence data . Classification systems based on molecular studies reveal three major groups or lineages of placental mammals— Afrotheria , Xenarthra and Boreoeutheria —which diverged in
4692-444: The closest thing to an official classification of mammals, despite its known issues. Most mammals, including the six most species-rich orders , belong to the placental group. The three largest orders in numbers of species are Rodentia : mice , rats , porcupines , beavers , capybaras , and other gnawing mammals; Chiroptera : bats; and Eulipotyphla : shrews , moles , and solenodons . The next three biggest orders, depending on
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#17327839710214784-1332: The divergence times between these three placental groups range from 105 to 120 million years ago, depending on the type of DNA used (such as nuclear or mitochondrial ) and varying interpretations of paleogeographic data. Monotremata Marsupialia Xenarthra Afrotheria Glires Euarchonta [REDACTED] Eulipotyphla Chiroptera Pholidota Carnivora [REDACTED] Perissodactyla [REDACTED] Artiodactyla [REDACTED] Monotremata [REDACTED] Paucituberculata [REDACTED] Didelphimorphia [REDACTED] Microbiotheria Notoryctemorphia [REDACTED] Peramelemorphia [REDACTED] Dasyuromorphia [REDACTED] Diprotodontia [REDACTED] Cingulata [REDACTED] Pilosa [REDACTED] Hyracoidea [REDACTED] Sirenia [REDACTED] Proboscidea [REDACTED] Tubulidentata [REDACTED] Macroscelidea [REDACTED] Afrosoricida [REDACTED] Eulipotyphla [REDACTED] Chiroptera [REDACTED] Pholidota [REDACTED] Carnivora [REDACTED] Perissodactyla [REDACTED] Artiodactyla [REDACTED] Scandentia [REDACTED] Lagomorpha [REDACTED] Urogenital triangle The urogenital triangle
4876-585: The earlier Triassic , despite the fact that Triassic fossils in the Haramiyida have been referred to the Mammalia since the mid-19th century. If Mammalia is considered as the crown group, its origin can be roughly dated as the first known appearance of animals more closely related to some extant mammals than to others. Ambondro is more closely related to monotremes than to therian mammals while Amphilestes and Amphitherium are more closely related to
4968-451: The end of the 20th century. However, since 1945, a large amount of new and more detailed information has gradually been found: The paleontological record has been recalibrated, and the intervening years have seen much debate and progress concerning the theoretical underpinnings of systematization itself, partly through the new concept of cladistics . Though fieldwork and lab work progressively outdated Simpson's classification, it remains
5060-447: The epithelium allows for an effective response from the immune system since antibodies and other immune components can easily reach the surface. The vaginal epithelium differs from the similar tissue of the skin. The epidermis of the skin is relatively resistant to water because it contains high levels of lipids. The vaginal epithelium contains lower levels of lipids. This allows the passage of water and water-soluble substances through
5152-411: The first time. The fetus begins to lose the support of the cervix when contractions begin. With cervical dilation reaching 10 cm to accommodate the head of the fetus, the head moves from the uterus to the vagina. The elasticity of the vagina allows it to stretch to many times its normal diameter in order to deliver the child. Vaginal births are more common, but if there is a risk of complications
5244-444: 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. 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
5336-406: The intermediate cells. The basal layer of the epithelium is the most mitotically active and reproduces new cells. The superficial cells shed continuously and basal cells replace them. Estrogen induces the intermediate and superficial cells to fill with glycogen . Cells from the lower basal layer transition from active metabolic activity to death ( apoptosis ). In these mid-layers of the epithelia,
5428-668: The larger Amniota clade. Early synapsids are referred to as " pelycosaurs ." The more advanced therapsids became dominant during the Guadalupian . Mammals originated from cynodonts , an advanced group of therapsids, during the Late Triassic to Early Jurassic . Mammals achieved their modern diversity in the Paleogene and Neogene periods of the Cenozoic era, after the extinction of non-avian dinosaurs , and have been
5520-409: The longer the woman is aroused. It reduces friction or injury that can be caused by insertion of the penis into the vagina or other penetration of the vagina during sexual activity. The vagina lengthens during the arousal, and can continue to lengthen in response to pressure; as the woman becomes fully aroused, the vagina expands in length and width, while the cervix retracts. With the upper two-thirds of
5612-440: The lumen outwards consists firstly of a mucosa of stratified squamous epithelium that is not keratinized , with a lamina propria (a thin layer of connective tissue ) underneath it. Secondly, there is a layer of smooth muscle with bundles of circular fibers internal to longitudinal fibers (those that run lengthwise). Lastly, is an outer layer of connective tissue called the adventitia . Some texts list four layers by counting
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#17327839710215704-466: The lymph nodes of concern are sometimes treated with radiation therapy administered to the patient's pelvic, inguinal lymph nodes, or both. Vaginal cancer and vulvar cancer are very rare, and primarily affect older women. Cervical cancer (which is relatively common) increases the risk of vaginal cancer, which is why there is a significant chance for vaginal cancer to occur at the same time as, or after, cervical cancer. It may be that their causes are
5796-457: The male condom or because it can slip into the vagina and spill semen. The vaginal lymph nodes often trap cancerous cells that originate in the vagina. These nodes can be assessed for the presence of disease. Selective surgical removal (rather than total and more invasive removal) of vaginal lymph nodes reduces the risk of complications that can accompany more radical surgeries. These selective nodes act as sentinel lymph nodes. Instead of surgery,
5888-440: The outer third of the vagina; their function is to provide the vagina with increased surface area for extension and stretching. The epithelium of the ectocervix (the portion the uterine cervix extending into the vagina) is an extension of, and shares a border with, the vaginal epithelium. The vaginal epithelium is made up of layers of cells, including the basal cells , the parabasal cells, the superficial squamous flat cells , and
5980-481: The outermost layer of the vaginal epithelium. This microbiome consists of species and genera, which typically do not cause symptoms or infections in women with normal immunity. The vaginal microbiome is dominated by Lactobacillus species. These species metabolize glycogen, breaking it down into sugar. Lactobacilli metabolize the sugar into glucose and lactic acid. Under the influence of hormones, such as estrogen, progesterone and follicle-stimulating hormone (FSH),
6072-403: The pelvic exam of a pregnant woman is a bluish tinge to the vaginal wall. Pelvic exams are most often performed when there are unexplained symptoms of discharge, pain, unexpected bleeding or urinary problems. During a pelvic exam, the vaginal opening is assessed for position, symmetry , presence of the hymen, and shape. The vagina is assessed internally by the examiner with gloved fingers, before
6164-621: The penis and helps to cause a man to experience orgasm and ejaculation , which in turn enables fertilization . An area in the vagina that may be an erogenous zone is the G-spot . It is typically defined as being located at the anterior wall of the vagina, a couple or few inches in from the entrance, and some women experience intense pleasure, and sometimes an orgasm, if this area is stimulated during sexual activity. A G-spot orgasm may be responsible for female ejaculation , leading some doctors and researchers to believe that G-spot pleasure comes from
6256-455: The perineal body and the pubovaginal part of the levator ani muscle. The vaginal opening (also known as the vaginal introitus and the Latin ostium vaginae ) is at the posterior end of the vulval vestibule , behind the urethral opening . The term introitus is more technically correct than "opening", since the vagina is usually collapsed, with the opening closed. The opening to the vagina
6348-716: The primary source of food for humans. This led to a major restructuring of human societies from nomadic to sedentary, with more co-operation among larger and larger groups, and ultimately the development of the first civilizations . Domesticated mammals provided, and continue to provide, power for transport and agriculture, as well as food ( meat and dairy products ), fur , and leather . Mammals are also hunted and raced for sport, kept as pets and working animals of various types, and are used as model organisms in science. Mammals have been depicted in art since Paleolithic times, and appear in literature, film, mythology, and religion. Decline in numbers and extinction of many mammals
6440-449: The release of plasma as transudate from the capillaries through the vaginal epithelium. Before and during ovulation , the mucous glands within the cervix secrete different variations of mucus, which provides an alkaline , fertile environment in the vaginal canal that is favorable to the survival of sperm . Following menopause, vaginal lubrication naturally decreases. Nerve endings in the vagina can provide pleasurable sensations when
6532-456: The same. Cervical cancer may be prevented by pap smear screening and HPV vaccines , but HPV vaccines only cover HPV types 16 and 18, the cause of 70% of cervical cancers. Some symptoms of cervical and vaginal cancer are dyspareunia , and abnormal vaginal bleeding or vaginal discharge, especially after sexual intercourse or menopause. However, most cervical cancers are asymptomatic (present no symptoms). Vaginal intracavity brachytherapy (VBT)
6624-407: The side of the vagina with the cervical branch of the uterine artery; this forms the azygos artery , which lies on the midline of the anterior and posterior vagina. Other arteries which supply the vagina include the middle rectal artery and the internal pudendal artery , all branches of the internal iliac artery. Three groups of lymphatic vessels accompany these arteries; the upper group accompanies
6716-428: The speculum is inserted, to note the presence of any weakness, lumps or nodules . Inflammation and discharge are noted if present. During this time, the Skene's and Bartolin's glands are palpated to identify abnormalities in these structures. After the digital examination of the vagina is complete, the speculum, an instrument to visualize internal structures, is carefully inserted to make the cervix visible. Examination of
6808-548: The therians; as fossils of all three genera are dated about 167 million years ago in the Middle Jurassic , this is a reasonable estimate for the appearance of the crown group. T. S. Kemp has provided a more traditional definition: " Synapsids that possess a dentary – squamosal jaw articulation and occlusion between upper and lower molars with a transverse component to the movement" or, equivalently in Kemp's view,
6900-430: The tissue. Keratinization happens when the epithelium is exposed to the dry external atmosphere. In abnormal circumstances, such as in pelvic organ prolapse , the mucosa may be exposed to air, becoming dry and keratinized. Blood is supplied to the vagina mainly via the vaginal artery , which emerges from a branch of the internal iliac artery or the uterine artery . The vaginal arteries anastamose (are joined) along
6992-407: The twenty to twenty-fourth week of development. If the lumen does not form, or is incomplete, membranes known as vaginal septa can form across or around the tract, causing obstruction of the outflow tract later in life. 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
7084-455: The two sublayers of the mucosa (epithelium and lamina propria) separately. The smooth muscular layer within the vagina has a weak contractive force that can create some pressure in the lumen of the vagina; much stronger contractive force, such as during childbirth, comes from muscles in the pelvic floor that are attached to the adventitia around the vagina. The lamina propria is rich in blood vessels and lymphatic channels. The muscular layer
7176-402: The urethral opening and associated parts of the external genitalia. 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. The vaginal and urethral openings are protected by the labia. When not sexually aroused , the vagina
7268-437: The use of condoms , and sometimes female condoms (which give women more control). Both types can help avert pregnancy by preventing semen from coming in contact with the vagina. There is, however, little research on whether female condoms are as effective as male condoms at preventing STIs, and they are slightly less effective than male condoms at preventing pregnancy, which may be because the female condom fits less tightly than
7360-442: The vagina and provide continuous, low dose and consistent drug levels in the vagina and throughout the body. Before the baby emerges from the womb, an injection for pain control during childbirth may be administered through the vaginal wall and near the pudendal nerve . Because the pudendal nerve carries motor and sensory fibers that innervate the pelvic muscles, a pudendal nerve block relieves birth pain. The medicine does not harm
7452-407: The vagina expanding and lengthening, the uterus rises into the greater pelvis , and the cervix is elevated above the vaginal floor, resulting in tenting of the mid-vaginal plane. This is known as the tenting or ballooning effect. As the elastic walls of the vagina stretch or contract , with support from the pelvic muscles, to wrap around the inserted penis (or other object), this creates friction for
7544-459: The vagina in a variety of ways. In addition to penile penetration, pleasure can come from masturbation , fingering , or specific sex positions (such as the missionary position or the spoons sex position ). Heterosexual couples may engage in fingering as a form of foreplay to incite sexual arousal or as an accompanying act, or as a type of birth control , or to preserve virginity . Less commonly, they may use non penile-vaginal sexual acts as
7636-593: The vagina is self-cleansing, it usually does not need special hygiene. Clinicians generally discourage the practice of douching for maintaining vulvovaginal health. Since the vaginal flora gives protection against disease, a disturbance of this balance may lead to infection and abnormal discharge. Vaginal discharge may indicate a vaginal infection by color and odor, or the resulting symptoms of discharge, such as irritation or burning. Abnormal vaginal discharge may be caused by STIs, diabetes, douches, fragranced soaps, bubble baths, birth control pills, yeast infection (commonly as
7728-447: The vagina is stimulated during sexual activity. Women may derive pleasure from one part of the vagina, or from a feeling of closeness and fullness during vaginal penetration. Because the vagina is not rich in nerve endings, women often do not receive sufficient sexual stimulation, or orgasm , solely from vaginal penetration. Although the literature commonly cites a greater concentration of nerve endings and therefore greater sensitivity near
7820-561: The vagina may also be done during a cavity search . Lacerations or other injuries to the vagina can occur during sexual assault or other sexual abuse . These can be tears, bruises, inflammation and abrasions. Sexual assault with objects can damage the vagina and X-ray examination may reveal the presence of foreign objects. If consent is given, a pelvic examination is part of the assessment of sexual assault. Pelvic exams are also performed during pregnancy, and women with high risk pregnancies have exams more often. Intravaginal administration
7912-404: The vaginal branches of the uterine artery; a middle group accompanies the vaginal arteries; and the lower group, draining lymph from the area outside the hymen, drain to the inguinal lymph nodes . Ninety-five percent of the lymphatic channels of the vagina are within 3 mm of the surface of the vagina. Two main veins drain blood from the vagina, one on the left and one on the right. These form
8004-763: The vaginal ecosystem undergoes cyclic or periodic changes. Vaginal health can be assessed during a pelvic examination , along with the health of most of the organs of the female reproductive system. Such exams may include the Pap test (or cervical smear). In the United States, Pap test screening is recommended starting around 21 years of age until the age of 65. However, other countries do not recommend pap testing in non-sexually active women. Guidelines on frequency vary from every three to five years. Routine pelvic examination on women who are not pregnant and lack symptoms may be more harmful than beneficial. A normal finding during
8096-426: The vaginal entrance (the outer one-third or lower third), some scientific examinations of vaginal wall innervation indicate no single area with a greater density of nerve endings. Other research indicates that only some women have a greater density of nerve endings in the anterior vaginal wall. Because of the fewer nerve endings in the vagina, childbirth pain is significantly more tolerable. Pleasure can be derived from
8188-464: The vaginal fluid can be caused by an overgrowth of bacteria as in bacterial vaginosis , or in the parasitic infection trichomoniasis , both of which have vaginitis as a symptom. Vaginal flora populated by a number of different bacteria characteristic of bacterial vaginosis increases the risk of adverse pregnancy outcomes. During a pelvic exam, samples of vaginal fluids may be taken to screen for sexually transmitted infections or other infections. Because
8280-420: The vaginal opening, were originally considered the primary source for vaginal lubrication, but further examination showed that they provide only a few drops of mucus . Vaginal lubrication is mostly provided by plasma seepage known as transudate from the vaginal walls. This initially forms as sweat-like droplets, and is caused by increased fluid pressure in the tissue of the vagina ( vasocongestion ), resulting in
8372-645: 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 other people 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 has 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 ,
8464-419: The word vagina is often used incorrectly to refer to the vulva or to the female genitals in general. The term vagina is from Latin vāgīna , meaning "sheath" or " scabbard ". The vagina may also be referred to as the birth canal in the context of pregnancy and childbirth . Although by its dictionary and anatomical definitions, the term vagina refers exclusively to the specific internal structure, it
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