the portion of the uterine endometrium that is shed every month is the
the functional layer
117506
Endometrium The endometrium is the inner epithelial layer, along with its mucous membrane, of the mammalian uterus. It has a basal layer and a functional layer; the functional layer thickens and then is shed during menstruation in humans, as well as some other mammals including apes, Old World monkeys, some species of bat, and the elephant shrew. In most other mammals the endometrium is reabsorbed in the estrous cycle. During pregnancy, the glands and blood vessels in the endometrium further increase in size and number. Vascular spaces fuse and become interconnected, forming the placenta, which supplies oxygen and nutrition to
Endometrium
117506
Endometrium The endometrium is the inner epithelial layer, along with its mucous membrane, of the mammalian uterus. It has a basal layer and a functional layer; the functional layer thickens and then is shed during menstruation in humans, as well as some other mammals including apes, Old World monkeys, some species of bat, and the elephant shrew. In most other mammals the endometrium is reabsorbed in the estrous cycle. During pregnancy, the glands and blood vessels in the endometrium further increase in size and number. Vascular spaces fuse and become interconnected, forming the placenta, which supplies oxygen and nutrition to
Endometrium
117508
the cavity of the uterus, and not in the lining of the Fallopian tubes. In the absence of progesterone, the arteries supplying blood to the functional layer constrict, so that cells in that layer become ischaemic and die, leading to menstruation. It is possible to identify the phase of the menstrual cycle by reference to either the ovarian cycle or the uterine cycle by observing microscopic differences at each phase—for example in the ovarian cycle: About 20,000 protein coding genes are expressed in human cells and some 70% of these genes are expressed in the normal endometrium. Just over 100
Endometrium
9232879
Uterine gland Tube-like uterine glands, lined by ciliated columnar epithelium, are found in the functional layer of the uterine endometrium. Their appearance varies during the menstrual cycle. During the proliferative phase, uterine glands appear long due to estrogen secretion by the ovaries. During the secretory phase, the uterine glands become very coiled with wide lumens and produce a glycogen-rich secretion. This change corresponds with an increase in blood flow to spiral arteries due to increased progesterone secretion from the corpus luteum. During the pre-menstrual phase, progesterone secretion decreases as the corpus luteum degenerates, which results in decreased blood flow to
Uterine gland
9232877
Uterine gland Tube-like uterine glands, lined by ciliated columnar epithelium, are found in the functional layer of the uterine endometrium. Their appearance varies during the menstrual cycle. During the proliferative phase, uterine glands appear long due to estrogen secretion by the ovaries. During the secretory phase, the uterine glands become very coiled with wide lumens and produce a glycogen-rich secretion. This change corresponds with an increase in blood flow to spiral arteries due to increased progesterone secretion from the corpus luteum. During the pre-menstrual phase, progesterone secretion decreases as the corpus luteum degenerates, which results in decreased blood flow to
Uterine gland
117520
stratum basalis and functionalis layers, and is also observed in the periovulatory period secondary to rising estradiol levels, and disappears after ovulation. Endometrium The endometrium is the inner epithelial layer, along with its mucous membrane, of the mammalian uterus. It has a basal layer and a functional layer; the functional layer thickens and then is shed during menstruation in humans, as well as some other mammals including apes, Old World monkeys, some species of bat, and the elephant shrew. In most other mammals the endometrium is reabsorbed in the estrous cycle. During pregnancy, the glands and blood vessels in the
Endometrium
4446833
anomalies are often but not always correlated with severity: adhesions restricted to only the cervix or lower uterus may block menstruation. Pain during menstruation and ovulation is sometimes experienced and can be attributed to blockages. It has been reported that 88% of AS cases occur after a D&C is performed on a recently pregnant uterus, following a missed or incomplete miscarriage, birth, or during an elective termination (abortion) to remove retained products of conception. The cavity of the uterus is lined by the endometrium. This lining is composed of two layers, the functional layer (adjacent to the uterine cavity) which
Asherman's syndrome
8904507
in their secretions. These changes reach their maximum about 7 days after ovulation. Furthermore, the surface of the endometrium produces a kind of rounded cells, which cover the whole area toward the uterine cavity. This happens about 9 to 10 days after ovulation. These cells are called decidual cells, which emphasises that the whole layer of them is shed off in every menstruation if no pregnancy occurs, just as leaves of deciduous trees. The uterine glands, on the other hand, decrease in activity and degenerate around 8 to 9 days after ovulation in absence of pregnancy. The decidual cells originate
Implantation (human embryo)
6420695
the endometrium is shed every 4 weeks, the granulomas are poorly formed. In human medicine, pyometra (also a veterinary condition of significance) is regarded as a form of chronic endometritis seen in elderly women causing stenosis of the cervical os and accumulation of discharges and infection. Symptom in chronic endometritis is blood stained discharge but in pyometra the patient complaints of lower abdominal pain. Pyometra describes an accumulation of pus in the uterine cavity. In order for pyometra to develop, there must be both an infection "and" blockage of cervix. Signs and symptoms include lower abdominal pain (suprapubic), rigors, fever,
Endometritis
1406156
Ovulation Ovulation is the release of eggs from the ovaries. In humans, this event occurs when the ovarian follicles rupture and release the secondary oocyte ovarian cells. After ovulation, during the luteal phase, the egg will be available to be fertilized by sperm. In addition, the uterine lining (endometrium) is thickened to be able to receive a fertilized egg. If no conception occurs, the uterine lining as well as blood will be shed during menstruation. In humans, ovulation occurs about midway through the menstrual cycle, after the follicular phase. The few days surrounding ovulation (from approximately days 10 to 18
Ovulation
6551068
Decidua The decidua is the uterine lining (endometrium) during a pregnancy, which forms the maternal part of the placenta. It is formed under the influence of progesterone and forms highly characteristic cells. The part of the decidua that interacts with the trophoblast is the "decidua basalis" (also called "decidua placentalis"), while the "decidua capsularis" grows over the embryo on the luminal side, enclosing it into the endometrium. The remainder of the decidua is termed the "decidua parietalis" or "decidua vera", and it will fuse with the decidua capsularis by the fourth month of gestation. Three morphologically distinct layers of the
Decidua
4598220
a rupture due to the location of placental attachment. During the third trimester of pregnancy, thinning of the lower uterine segment or contractions caused by cervical dilation can increase the amount of stress placed on the placental attachment to the uterine wall. In patients with placenta praevia, these stresses can cause detachment of the placenta from the uterine wall causing haemorrhaging. To prevent further haemorrhaging patients with major placental praevia are recommended to have a caesarean delivery. During pregnancy the layer of endometrium that attaches directly to developing blastocyst becomes the maternal portion of the placenta, also known as the
Antepartum bleeding
14527354
the patient's amenorrhea is likely to be due to either a) low serum estradiol, b) hypothalamic-pituitary axis dysfunction, c) a nonreactive endometrium, or d) a problem with the uterine outflow tract, such as cervical stenosis or uterine synechiae (Asherman's syndrome). In order to distinguish between hypoestrogenism or a uterine outflow tract problem/nonreactive endometrium, estrogen may be administered followed by a course of progestin in order to induce withdrawal bleeding. If the patient experiences withdrawal bleeding with the combined estrogen/progestin therapy, then the amenorrhea is likely due to low estrogen. Progestin challenge Progestin challenge, or progesterone withdrawal test is a test
Progestin challenge
117515
the body with human chorionic gonadotropin (HCG). HCG provides continued feedback throughout pregnancy by maintaining the corpus luteum, which will continue its role of releasing progesterone and estrogen. The endometrial lining is either reabsorbed (estrous cycle) or shed (menstrual cycle). In the latter case, the process of shedding involves the breaking down of the lining, the tearing of small connective blood vessels, and the loss of the tissue and blood that had constituted it through the vagina. The entire process occurs over a period of several days. Menstruation may be accompanied by a series of uterine contractions; these help expel
Endometrium
15114921
pregnancy, uterine serpin protein can be found in the lumenal epithelium as well, perhaps as glandular epithelial cells move to the uterine lumen. The major regulator of uterine serpin gene expression is progesterone. In the cow, estrogen can also increase uterine serpin gene expression. In addition to expression in the endometrium, bovine uterine serpin is also expressed in the ovary (follicles, corpus luteum, and cumulus-oocyte complex) and by cotyledons of the placenta. There are two lines of evidence to indicate that uterine serpins do not function as protease inhibitors. Uterine serpins from the sheep and pig are not inhibitory towards
Uterine serpin
1981588
gynecologic hemorrhage, namely bleeding from a miscarriage or an ectopic pregnancy, while it actually represents obstetrical bleeding. However, from a practical view, early pregnancy bleeding is usually handled like a gynecological hemorrhage. Causes of gynecologic bleeding include: Anovulation is a common cause of gynecological hemorrhage. Under the influence of estrogen the endometrium (uterine lining) is stimulated and eventually such lining will be shed off (estrogen breakthrough bleeding). The anovulation chapter discusses its multiple possible causes. Longstanding anovulation can also lead to endometrial hyperplasia and facilitate the development of endometrial cancer. Women with a bleeding disorder may be prone to more
Gynecologic hemorrhage
2452220
experience increased pain during their periods. Other skeletal abnormalities, such as scoliosis (sometimes caused by spina bifida) might be possible contributors as well. During a woman's menstrual cycle, the endometrium thickens in preparation for potential pregnancy. After ovulation, if the ovum is not fertilized and there is no pregnancy, the built-up uterine tissue is not needed and thus shed. Molecular compounds called prostaglandins are released during menstruation, due to the destruction of the endometrial cells, and the resultant release of their contents. Release of prostaglandins and other inflammatory mediators in the uterus cause the uterus to contract. These substances are
Dysmenorrhea
8904517
the surface of trophoblast cells. An in vitro model of implantation developed by Genbacev "et al.," gave evidence to support the hypothesis that L-selectin mediates apposition of the blastocyst to the uterine epithelium by interacting with its ligands. Adhesion is a much stronger attachment to the endometrium than the loose apposition. The trophoblasts adhere by penetrating the endometrium, with protrusions of trophoblast cells. There is massive communication between the blastocyst and the endometrium at this stage. The blastocyst signals to the endometrium to adapt further to its presence, e.g. by changes in the cytoskeleton of decidual cells. This, in turn,
Implantation (human embryo)
19596726
Investigations into the role of the uterine microbiome in the development of the infant microbiome are ongoing. Uterine microbiome The uterine microbiome is the commensal, nonpathogenic, bacteria, viruses, yeasts/fungi present in a healthy uterus, amniotic fluid and endometrium and the specific environment which they inhabit. It has been only recently confirmed that the uterus and its tissues are not sterile. Due to improved 16S rRNA gene sequencing techniques, detection of bacteria that are present in low numbers is possible. Using this procedure that allows the detection of bacteria that cannot be cultured outside the body, studies of microbiota present in
Uterine microbiome
5023400
Myometrium The myometrium is the middle layer of the uterine wall, consisting mainly of uterine smooth muscle cells (also called uterine myocytes), but also of supporting stromal and vascular tissue. Its main function is to induce uterine contractions. The myometrium is located between the endometrium (the inner layer of the uterine wall), and the serosa or perimetrium (the outer uterine layer). Myometrium has 3 layers: outer longitudinal smooth muscles, middle crisscrossing (figure of eight) muscle fibres, and inner circular fibres. Middle crisscross fibres act as living ligature during involution of the uterus and prevent blood loss. The inner one-third of
Myometrium
5142867
Approximately every 28 days, the pituitary gland releases a hormone that stimulates some of the ova to develop and grow. One ovum is released and it passes through the Fallopian tube into the uterus. Hormones produced by the ovaries prepare the uterus to receive the ovum. The lining of the uterus, called the endometrium, and unfertilized ova are shed each cycle through the process of menstruation. If the ovum is fertilized by sperm, it attaches to the endometrium and the fetus develops. The development of the reproductive system and the development of the urinary system are closely tied in with
Human reproductive system
19596722
Uterine microbiome The uterine microbiome is the commensal, nonpathogenic, bacteria, viruses, yeasts/fungi present in a healthy uterus, amniotic fluid and endometrium and the specific environment which they inhabit. It has been only recently confirmed that the uterus and its tissues are not sterile. Due to improved 16S rRNA gene sequencing techniques, detection of bacteria that are present in low numbers is possible. Using this procedure that allows the detection of bacteria that cannot be cultured outside the body, studies of microbiota present in the uterus are expected to increase. Bacteria, viruses and one genus of yeasts are a normal part
Uterine microbiome
2566838
blastocyst has a diameter of about 0.1–0.2 mm and comprises 200–300 cells following rapid cleavage (cell division). About 1 day after blastocyst formation (5–6 days post-fertilization), which is when the blastocyst usually reaches the uterus, the blastocyst begins to embed into the endometrium of the uterine wall where it will undergo further developmental processes, including gastrulation. Embedding of the blastocyst into the endometrium requires that it hatches from the zona pellucida, which prevents adherence to the oviduct as the pre-embryo makes its way to the uterus. The blastocyst is completely embedded in the endometrium only 11–12 days after fertilization. The
Blastocyst
8904508
from the stromal cells that are always present in the endometrium. However, the decidual cells make up a new layer, the decidua. The rest of the endometrium, in addition, expresses differences between the luminal and the basal sides. The luminal cells form the zona compacta of the endometrium, in contrast to the basalolateral zona spongiosa, which consists of the rather spongy stromal cells. Decidualization succeeds predecidualization if pregnancy occurs. This is an expansion of it, further developing the uterine glands, the zona compacta and the epithelium of decidual cells lining it. The decidual cells become filled with lipids and glycogen
Implantation (human embryo)
117513
functions to prevent adhesions between the opposed walls of the myometrium, thereby maintaining the patency of the uterine cavity. During the menstrual cycle or estrous cycle, the endometrium grows to a thick, blood vessel-rich, glandular tissue layer. This represents an optimal environment for the implantation of a blastocyst upon its arrival in the uterus. The endometrium is central, echogenic (detectable using ultrasound scanners), and has an average thickness of 6.7 mm. During pregnancy, the glands and blood vessels in the endometrium further increase in size and number. Vascular spaces fuse and become interconnected, forming the placenta, which supplies oxygen and
Endometrium
117510
are also expressed in other types of female tissue types, such as the cervix, fallopian tubes, ovaries and breast. The uterus and endometrium was for a long time thought to be sterile. The cervical plug of mucosa was seen to prevent the entry of any microorganisms ascending from the vagina. In the 1980s this view was challenged when it was shown that uterine infections could arise from weaknesses in the barrier of the cervical plug. Organisms from the vaginal microbiota could enter the uterus during uterine contractions in the menstrual cycle. Further studies sought to identify microbiota specific to the
Endometrium
19611528
in the process of menstruation. In endometriosis, some endometrial tissue is found in other parts of the body; most often the pelvis and abdomen, the central nervous system, the nasal passages, skin and thorax. At these other 'ectopic' sites, endometrium tissue still responds to hormones with normal cyclical changes - bleeding roughly every 28 days. Current theories describe the causes of extra-uterine endometriosis state that intra-abdominal and pelvic endometriosis is due to retrograde menstruation. This is thought to happen when menstrual debris may travel up through the fallopian tubes instead of out the cervix and vagina. When this occurs, endometrial
Thoracic endometriosis
12604995
Uterine clear-cell carcinoma Uterine clear-cell carcinoma (CC) is a rare form of endometrial cancer with distinct morphological features on pathology; it is aggressive and has high recurrence rate. Like uterine papillary serous carcinoma CC does not develop from endometrial hyperplasia and is not hormone sensitive, rather it arises from an atrophic endometrium. Such lesions belong to the type II endometrial cancers. The lesion is found in patients who present typically with abnormal or postmenopausal bleeding or discharge. Such bleeding is followed by further evaluation leading to a tissue diagnosis, usually done by a dilatation and curettage (D&C). A work-up to
Uterine clear-cell carcinoma
12604998
involvement IIIC2 Para-aortic involvement IVA Tumor invasion bladder and/or bowel mucosa IVB Distant metastases including abdominal metastases and/or inguinal lymph nodes Uterine clear-cell carcinoma Uterine clear-cell carcinoma (CC) is a rare form of endometrial cancer with distinct morphological features on pathology; it is aggressive and has high recurrence rate. Like uterine papillary serous carcinoma CC does not develop from endometrial hyperplasia and is not hormone sensitive, rather it arises from an atrophic endometrium. Such lesions belong to the type II endometrial cancers. The lesion is found in patients who present typically with abnormal or postmenopausal bleeding or discharge. Such bleeding
Uterine clear-cell carcinoma
4446830
was carried out by Israeli gynecologist Joseph Asherman. A number of other terms have been used to describe the condition and related conditions including: uterine/cervical atresia, traumatic uterine atrophy, sclerotic endometrium, and endometrial sclerosis. There isn't any one cause of AS. Risk factors can include myomectomy, Cesarean section, infections, age, genital tuberculosis, and obesity. Genetic predisposition to AS is being investigated. There are also studies that show that a severe pelvic infection, independent of surgery may cause AS . AS can develop even if the woman has not had any uterine surgeries, trauma, or pregnancies. While rare in North America
Asherman's syndrome
331628
antibiotics (usually doxycycline) are given to prevent infection of the Fallopian tubes (salpingitis) or endometrium (endometritis). Postoperative pain is usually minimal and managed with NSAIDs. In cases of uterine atony and corresponding blood loss, methergine or misoprostol can be given to encourage uterine contraction and achieve hemostasis. Patients who have recently undergone an intact D&E are monitored for signs of coagulopathy, uterine perforation, uterine atony, retained tissue, or hemorrhage. The term "partial-birth abortion" is primarily used in political discourse—chiefly regarding the legality of abortion in the United States. The term is not recognized as a medical term by the American
Intact dilation and extraction
15918608
infertile. Some anthropologists have questioned the energy cost of rebuilding the endometrium every fertility cycle. However, anthropologist Beverly Strassmann has proposed that the energy savings of not having to "continuously" maintain the uterine lining more than offsets energy cost of having to rebuild the lining in the next fertility cycle, even in species such as humans where much of the lining is lost through bleeding (overt menstruation) rather than reabsorbed (covert menstruation). However, even in humans, much of it is re-absorbed. Many have questioned the evolution of overt menstruation in humans and related species, speculating on what advantage there could
Menstruation (mammal)
6551073
of the decidua, chronic deciduitis, is associated with pre-term labour. The word comes . Decidua The decidua is the uterine lining (endometrium) during a pregnancy, which forms the maternal part of the placenta. It is formed under the influence of progesterone and forms highly characteristic cells. The part of the decidua that interacts with the trophoblast is the "decidua basalis" (also called "decidua placentalis"), while the "decidua capsularis" grows over the embryo on the luminal side, enclosing it into the endometrium. The remainder of the decidua is termed the "decidua parietalis" or "decidua vera", and it will fuse with the
Decidua
4468057
In other cases, menstruation may be fairly regular (eumenorrhea), or more frequent (intervals < 21 days), or there may be a loss of menstrual pattern (menorrhagia, dysfunctional uterine bleeding). Normal menstrual bleeding in the ovulatory cycle is a result of a decline in progesterone due to the demise of the corpus luteum. It is thus a progesterone withdrawal bleeding. As there is no progesterone in the anovulatory cycle, bleeding is caused by the inability of estrogen — that needs to be present to stimulate the endometrium in the first place — to support a growing endometrium. Anovulatory bleeding is hence
Anovulatory cycle
2813045
is essential for establishing and maintaining pregnancy in females. The corpus luteum secretes progesterone, which is a steroid hormone responsible for the decidualization of the endometrium (its development) and maintenance, respectively. It also produces relaxin, a hormone responsible for softening of the pubic symphysis which helps in parturition. If the egg is not fertilized, the corpus luteum stops secreting progesterone and decays (after approximately 10 days in humans). It then degenerates into a corpus albicans, which is a mass of fibrous scar tissue. The uterine lining (endometrium) is expelled through the vagina (in mammals that go through a menstrual cycle).
Corpus luteum
117516
the menstrual endometrium. In case of implantation, however, the endometrial lining is neither absorbed nor shed. Instead, it remains as "decidua". The decidua becomes part of the placenta; it provides support and protection for the gestation. If there is inadequate stimulation of the lining, due to lack of hormones, the endometrium remains thin and inactive. In humans, this will result in amenorrhea, or the absence of a menstrual period. After menopause, the lining is often described as being atrophic. In contrast, endometrium that is chronically exposed to estrogens, but not to progesterone, may become hyperplastic. Long-term use of oral contraceptives
Endometrium
15114918
Uterine serpin Uterine serpins are members of the A clade of the serine protease inhibitor (serpin) superfamily of proteins and are encoded by the SERPINA14 gene. Uterine serpins are produced by the endometrium of a restricted group of mammals under the influence of progesterone or estrogen. These proteins appear to be inactive protease inhibitors and may function during pregnancy to regulate immune function or participate in transplacental transport. Uterine serpins were originally described in the uterine secretions of unilaterally-pregnant sheep as a pair of 57 kDa and 55 kDa glycoproteins. Termed uterine milk proteins, their identification as members of the
Uterine serpin
15114924
populations. Uterine serpin Uterine serpins are members of the A clade of the serine protease inhibitor (serpin) superfamily of proteins and are encoded by the SERPINA14 gene. Uterine serpins are produced by the endometrium of a restricted group of mammals under the influence of progesterone or estrogen. These proteins appear to be inactive protease inhibitors and may function during pregnancy to regulate immune function or participate in transplacental transport. Uterine serpins were originally described in the uterine secretions of unilaterally-pregnant sheep as a pair of 57 kDa and 55 kDa glycoproteins. Termed uterine milk proteins, their identification as members of
Uterine serpin
8904506
blastocyst can still be eliminated by being flushed out of the uterus. Scientists have hypothesized that the hormones cause a swelling that fills the flattened out uterine cavity just prior to this stage, which may also help press the blastocyst against the endometrium. The implantation window may also be initiated by other preparations in the endometrium of the uterus, both structurally and in the composition of its secretions. To enable implantation, the uterus goes through changes in order to be able to receive the conceptus. The endometrium increases thickness, becomes vascularized and its glands grow to be tortuous and boosted
Implantation (human embryo)
20907283
communication can lead to an unsuccessful implantation and a further unsuccessful pregnancy . During implantation, the embryo must cross the epithelial layer of the maternal endometrium before invading and implanting in the stroma layer. Maternal factors, including congenital uterine abnormalities, fibroids, endometrial polyps, intrauterine adhesions, adenomyosis, thrombophilia and endometriosis, can reduce the chances of implantation and result in RIF. Congenital uterine abnormalities are irregularities in the uterus which occur during the mothers foetal development. Two genes have been identified to assist in the development and receptivity of the uterus and endometrium, Hoxa10 and Hoxa11. Hoxa10 has been shown to change
Repeated implantation failure
2383618
of deaths caused by colon cancer due to adenomatous polyps. While there are risks of complications associated with colonoscopies, those risks are extremely low at approximately 0.35 percent. For comparison, the lifetime risk of developing colon cancer is around 6 percent. As there is a small likelihood of recurrence, surveillance after polyp removal is recommended. An endometrial polyp or uterine polyp is a polyp or lesion in the lining of the uterus (endometrium) that takes up space within the uterine cavity. Commonly occurring, they are experienced by up to 10% of women. They may have a large flat base (sessile)
Polyp (medicine)
8904519
and penetrate into the endometrium. As these trophoblast cells penetrate, they differentiate to become a new type of cells, syncytiotrophoblast. The prefix syn- refers to the transformation that occurs as the boundaries between these cells disappear to form a single mass of many cell nuclei (a syncytium). The rest of the trophoblasts, surrounding the inner cell mass, are hereafter called cytotrophoblasts. Invasion continues with the syncytiotrophoblasts reaching the basal membrane beneath the decidual cells, penetrating it and further invading into the uterine stroma. Finally, the whole embryo is embedded in the endometrium. Eventually, the syncytiotrophoblasts come into contact with maternal
Implantation (human embryo)
8904512
the secretion from its epithelial glands changes. This change is induced by increased levels of progesterone from the corpus luteum. The target of the secretions is the embryoblast, and has several functions on it. The embryoblast spends approximately 72 hours in the uterine cavity before implanting. In that time, it cannot receive nourishment directly from the blood of the mother, and must rely on secreted nutrients into the uterine cavity, e.g. iron and fat-soluble vitamins. In addition to nourishment, the endometrium secretes several steroid-dependent proteins, important for growth and implantation. Cholesterol and steroids are also secreted. Implantation is further facilitated
Implantation (human embryo)
8904514
plasmin. Plasminogen, the plasmin precursor, is found in the uterine cavity, and blastocyst factors contribute to its conversion to active plasmin. This hypothesis is supported by lytic effects in vitro by plasmin. Furthermore, plasmin inhibitors also inhibit the entire zona hatching in rat experiments. The very first, albeit loose, connection between the blastocyst and the endometrium is called the apposition. On the endometrium, the apposition is usually made where there is a small crypt in it, perhaps because it increases the area of contact with the rather spherical blastocyst. On the blastocyst, on the other hand, it occurs at a
Implantation (human embryo)
19902614
of the female reproductive system, particularly postpartum metritis. Using dairy cattle, he identified the bacteria that cause uterine disease, including novel strains of Escherichia coli that are adapted to the uterine environment. In addition, Sheldon showed that the bacterium Trueperella pyogenes becomes a pathogen in the uterus by secreting a cholesterol-dependent cytolysin that damages stromal cells, once the epithelium is damaged after parturition. Sheldon uncovered the role for the innate immune system in the endometrium of the uterus, showing that epithelial and stromal cells, as well as the expected immune cells, have roles in host-pathogen interactions. Sheldon was the first
Martin Sheldon
15442311
order to stabilize the endometrial lining to allow for blastocyst attachment. The dramatic increase in trophoblastic and corpus luteal hCG synthesis signals both blastocyst and corpus luteal production of P4, crucial for the maintenance of the endometrium. hCG secreted by cytotrophoblastic cells of the blastocyst controls endometrial tissue remodeling by both activation of matrix matalloproteinases (MMP) that control the maternal extracellular matrix and inhibition of tissue-inhibitors of matrix-metalloproteinases (TIMP). hCG mediates invasion and attachment to the endometrium. Low levels of hCG increase risk of pre-eclampsia. Uterine angiogenesis is upregulated by human chorionic gonadotropin and progesterone and downregulated by estrogen. The
Endocrinology of reproduction
4562019
causes, ranging from being entirely asymptomatic 33% of the time to being a severe and debilitating condition in some cases. Women with adenomyosis typically first report symptoms when they are between 40 and 50, but symptoms can occur in younger women. Symptoms and the estimated percent affected may include: Clinical signs of adenomyosis may include: Women with adenomyosis are also more likely to have other uterine conditions, including: The cause of adenomyosis is unknown, although it has been associated with any sort of uterine trauma that may break the barrier between the endometrium and myometrium, known as the junctional zone,
Adenomyosis
2245176
disabilities have had hysterectomies though this treatment is controversial at best. In the United States, specific cases of sterilization due to developmental disabilities have been found by state-level Supreme Courts to violate the patient's constitutional and common law rights. Many types of reproductive system cancers are treated surgically. These include uterine, cervical, ovarian, or endometrium tumors, as well as uterine fibroids that do not respond to more conservative treatment options. In 1995, the short-term mortality (within 40 days of surgery) was reported at 0.38 cases per 1000 when performed for benign causes. Risks for surgical complications were presence of fibroids,
Hysterectomy
4575908
vaginam" (Latin: through the vagina) (PV) typically arises from the lining of the uterus (endometrium), but may arise from uterine or cervical lesions, the vagina, and rarely from the fallopian tube. During pregnancy it is usually but not always related to the pregnancy itself. Rarely, the blood may arise from the urinary tract (hematuria), although most women can identify the difference. It can also be a sign of vaginal cancer or uterine cancer. Some women experience postcoital bleeding that occurs after sexual intercourse. There are many potential causes for abnormal vaginal bleeding. Bleeding before the expected time of menarche could
Vaginal bleeding
3526067
cervix, which was open during her heat, begins to close, and the inner lining begins to adapt back to normal. However, cystic hyperplasia of the endometrium (inner lining of the uterus) – known as cystic endometrial hyperplasia (CEH) – may occur at this time for some animals, as an inappropriate response to progesterone. Under these circumstances, bacteria (especially "E. coli") that have migrated from the vagina into the uterus find the environment favorable to growth, especially since progesterone also causes mucus secretion, closes the cervix (preventing uterine drainage), and decreases uterine contractility. The condition of the cervix is a major
Pyometra
492045
menstruation. Schools can be an appropriate place for menstrual education to take place. Programs led by peers or third-party agencies are another option. Most female mammals have an estrous cycle, yet only ten primates species, four bats species, the elephant shrew, and the spiny mouse have a menstrual cycle. The relatedness of these groups suggests that four distinct evolutionary events have caused menstruation to arise. Some anthropologists have questioned the energy cost of rebuilding the endometrium every fertility cycle. It has proposed that the energy savings of not having to continuously maintain the uterine lining more than offsets energy cost
Menstruation
7000665
of the embryo into the uterine wall and involves the remodeling of blood vessels in order to supply the needed amount of blood. In humans, placentation takes place 7–8 days after fertilization. In humans, the placenta develops in the following manner. Chorionic villi (from the embryo) on the embryonic pole grow, forming chorion frondosum. Villi on the opposite side (abembryonic pole) degenerate and form the chorion laeve (or chorionic laevae), a smooth surface. The endometrium (from the mother) over the chorion frondosum (this part of the endometrium is called the decidua basalis) forms the decidual plate. The decidual plate is
Placentation
3940038
lipid metabolism but not on breast and uterine endometrium. It is well tolerated and displays no increase in hot flush incidences, uterine hypertrophy or breast tenderness. [[File:Ospemifene 2.png|thumb|200px|Figure 13: Chemical structure of ospemifene. Ethoxy side chain ends with a hydroxy group (red) instead of a dimethylamino group as with first-generation SERMs.]] Ospemifene (Z-2-(4-(4-chloro-1,2-diphenyl-but-1-enyl)phenoxy)ethanol; see figure 13) is a triphenylethylene and a known metabolite of toremifene. It´s structurally very similar to tamoxifen and toremifene. Ospemifene does not have 2-(dimethylamino)ethoxy group as tamoxifen. Structure–activity relationship studies shoved that by removing that group of tamoxifen agonistic activity in the uterus was significantly reduced,
Selective estrogen receptor modulator
117514
nutrition to the embryo and fetus. The endometrial lining undergoes cyclic regeneration. Humans, apes, and some other species display the menstrual cycle, whereas most other mammals are subject to an estrous cycle. In both cases, the endometrium initially proliferates under the influence of estrogen. However, once ovulation occurs, the ovary (specifically the corpus luteum) will produce much larger amounts of progesterone. This changes the proliferative pattern of the endometrium to a secretory lining. Eventually, the secretory lining provides a hospitable environment for one or more blastocysts. Upon fertilization, the egg may implant into the uterine wall and provide feedback to
Endometrium
10296533
can be made by endometrial biopsy, which is done in the office setting or through curettage of the uterine cavity to obtain endometrial tissue for histopathologic analysis. A workup for endometrial disease may be prompted by abnormal uterine bleeding, or the presence of atypical glandular cells on a pap smear. Treatment of endometrial hyperplasia is individualized, and may include hormonal therapy, such as cyclic or continuous progestin therapy, or hysterectomy. Endometrial hyperplasia Endometrial hyperplasia is a condition of excessive proliferation of the cells of the endometrium, or inner lining of the uterus. Most cases of endometrial hyperplasia result from high
Endometrial hyperplasia
7206569
Hashimoto's thyroiditis is the most common thyroid disease and is characterized by abundant lymphocyte infiltrate and thyroid impairment. Recent research suggests a potential role for HHV-6 (possibly variant A) in the development or triggering of Hashimoto's thyroiditis. The role of HHV-6 during pregnancy leading to inflammation in the amniotic cavity has been studied. HHV-6A DNA was found in the endometrium of almost half of a group of infertile women, but in none of the fertile control group. Natural killer cells specific for HHV-6A, and high uterine levels of certain cytokines, were also found in the endometrium of the infertile women
Human herpesvirus 6
18807658
a lateral incision of the uterine walls, and can return the organ to a normal morphology, while improving the patient's former reproductive performance. It is considered a low-risk procedure, and can also improve term delivery rate by up to 10-fold, as long as the endometrium is considered to be in good condition. However, risks after the procedure include placenta accreta, Asherman's syndrome and severe haemorrhage. T-shaped uterus A t-shaped uterus is a type of uterine malformation wherein the uterus is shaped resembling the letter T. This is typically observed in DES-exposed women. It is recognised in the ESHRE/ESGE classification, and
T-shaped uterus
893761
begins, symptoms of premenstrual syndrome (PMS) such as breast tenderness and irritability generally decrease. Many sanitary products are marketed to women for use during their menstruation. The proliferative phase is the second phase of the uterine cycle when estrogen causes the lining of the uterus to grow, or proliferate, during this time. As they mature, the ovarian follicles secrete increasing amounts of estradiol, and estrogen. The estrogens initiate the formation of a new layer of endometrium in the uterus, histologically identified as the proliferative endometrium. The estrogen also stimulates crypts in the cervix to produce fertile cervical mucus, which may
Menstrual cycle
7238743
use. They arise from interstitial cytotrophoblasts from the process of phenocopying. This changes the phenotype of these cells from epithelial to endothelial. Endovascular cytotrophoblasts, like their interstitial predecessor, are non-proliferating and invasive. Proper cytotrophoblast function is essential in the implantation of a blastocyst. After hatching, the embryonic pole of the blastocyst faces the uterine endometrium. Once they make contact the trophoblast begins to rapidly proliferate. The cytotrophoblast secretes proteolytic enzymes to break down the extracellular matrix between the endometrial cells to allow finger-like projections of trophoblast to penetrate through. Projections of cytotrophoblast and syncytiotrophoblast pull the embryo into the endometrium
Cytotrophoblast
5257155
that releases sex hormones including estrogens and progesterone. However, species vary significantly in the detailed functioning. One difference is that animals that have estrous cycles resorb the endometrium if conception does not occur during that cycle. Animals that have menstrual cycles shed the endometrium through menstruation instead. Another difference is sexual activity. In species with estrous cycles, females are generally only sexually active during the estrus (oestrus) phase of their cycle . This is also referred to as being "in heat". In contrast, females of species with menstrual cycles can be sexually active at any time in their cycle, even
Estrous cycle
14468859
Endometrial stromal sarcoma Endometrial stromal sarcoma is a malignant subtype of endometrial stromal tumor arising from the stroma (connective tissue) of the endometrium rather than the glands. There are three grades for endometrial stromal tumors, as follows. It was previously known as "endolymphatic stromal myosis" because of diffuse infiltration of myometrial tissue or the invasion of lymphatic channels. Low-grade endometrial stromal sarcoma consists of cells resembling normal proliferative phase endometrium, but with infiltration or vascular invasion. These behave less aggressively, sometimes metastasizing, with cancer stage the best predictor of survival. The cells express estrogen/progesterone-receptors. Undifferentiated uterine sarcoma, or undifferentiated (high-grade)
Endometrial stromal sarcoma
8904505
The implantation window occurs around 6 days after the peak in luteinizing hormone levels. With some disparity between sources, it has been stated to occur from 7 days after ovulation until 9 days after ovulation, or days 6-10 postovulation. On average, it occurs during the 20th to the 23rd day after the last menstrual period. The implantation window is characterized by changes to the endometrium cells, which aid in the absorption of the uterine fluid. These changes are collectively known as the plasma membrane transformation and bring the blastocyst nearer to the endometrium and immobilize it. During this stage the
Implantation (human embryo)
8022037
periphery and have immediate effector functions upon encountering antigen. High expression of L-selectin on human bone marrow progenitor cells is an early sign of cells becoming committed to lymphoid differentiation. L-selectin is also present on the surface of human embryo trophoblasts prior to implantation into the uterus. Similar to its function in lymphocytes, L-selectin acts as a receptor to facilitate adhesion of the embryo to the site of invasion on the surface epithelium of the uterine endometrium. The embryo secretes human chorionic gonadotropin (hCG), which downregulates anti-adhesion factor, MUC-1, located on the uterine epithelium at the site of invasion. Removal
L-selectin
649898
be regulated with a contraceptive pill. The purpose of regulating menstruation, in essence, is for the woman's convenience, and perhaps her sense of well-being; there is no medical requirement for regular periods, as long as they occur sufficiently often. If a regular menstrual cycle is not desired, then therapy for an irregular cycle is not necessarily required. Most experts say that, if a menstrual bleed occurs at least every three months, then the endometrium (womb lining) is being shed sufficiently often to prevent an increased risk of endometrial abnormalities or cancer. If menstruation occurs less often or not at all,
Polycystic ovary syndrome
492023
as premenstrual molimina. Many women experience painful cramps, also known as dysmenorrhea, during menstruation. Pain results from ischemia and muscle contractions. Spiral arteries in the secretory endometrium constrict, resulting in ischemia to the secretory endometrium. This allows the uterine lining to slough off. The myometrium contracts spasmodically in order to push the menstrual fluid through the cervix and out of the vagina. The contractions are mediated by a release of prostaglandins. Painful menstrual cramps that result from an excess of prostaglandin release are referred to as primary dysmenorrhea. Primary dysmenorrhea usually begins within a year or two of menarche, typically
Menstruation
893762
be noticed by women practicing fertility awareness. The secretory phase is the final phase of the uterine cycle and it corresponds to the luteal phase of the ovarian cycle. During the secretory phase, the corpus luteum produces progesterone, which plays a vital role in making the endometrium receptive to implantation of the blastocyst and supportive of the early pregnancy, by increasing blood flow and uterine secretions and reducing the contractility of the smooth muscle in the uterus; it also has the side effect of raising the woman's basal body temperature. While some forms of birth control do not affect the
Menstrual cycle
3208491
in direct stimulation of the hypothalamic-pituitary axis. It also has an effect on cervical mucus quality and uterine mucosa, which might affect sperm penetration and survival, hence its early administration during the menstrual cycle. Clomifene citrate is a very efficient ovulation inductor, and has a success rate of 67%. Nevertheless, it only has a 37% success rate in inducing pregnancy. This difference may be due to the anti-estrogenic effect which clomifene citrate has on the endometrium, cervical mucus, uterine blood flow, as well as the resulting decrease in the motility of the fallopian tubes and the maturation of the oocytes.
Anovulation
2452221
thought to be a major factor in primary dysmenorrhea. When the uterine muscles contract, they constrict the blood supply to the tissue of the endometrium, which, in turn, breaks down and dies. These uterine contractions continue as they squeeze the old, dead endometrial tissue through the cervix and out of the body through the vagina. These contractions, and the resulting temporary oxygen deprivation to nearby tissues, are responsible for the pain or "cramps" experienced during menstruation. Compared with other women, women with primary dysmenorrhea have increased activity of the uterine muscle with increased contractility and increased frequency of contractions. The
Dysmenorrhea
4080211
cause abnormally heavy flow as progesterone stabilizes the endometrium and inhibits synthesis of prostaglandin F2-alpha; increased levels of tissue plasminogen activator (TPA) (a fibrinolytic enzyme) lead to more fibrinolysis. 10% of cases occur in women who are ovulating, but progesterone secretion is prolonged because estrogen levels are low. This causes irregular shedding of the uterine lining and break-through bleeding. Some evidence has associated Ovulatory DUB with more fragile blood vessels in the uterus. It may represent a possible endocrine dysfunction, resulting in menorrhagia or metrorrhagia. Mid-cycle bleeding may indicate a transient estrogen decline, while late-cycle bleeding may indicate progesterone deficiency.
Abnormal uterine bleeding
9148672
Decidualization Decidualization is a process that results in significant changes to cells of the endometrium in preparation for, and during, pregnancy. This includes morphological and functional changes to endometrial stromal cells (ESCs), the presence of decidual white blood cells (leukocytes), and vascular changes to maternal arteries. The sum of these changes results in the endometrium changing into a structure called the decidua. In humans, the decidua is shed during the third phase of birth. Decidualization plays an important role in promoting placenta formation between a mother and her fetus by mediating the invasiveness of trophoblast cells. It also triggers the
Decidualization
11834922
scanty menstruation perhaps best explained by assuming the presence of an unusual arrangement, or relative insensitivity, of the endometrial vascular apparatus. Reduced menstrual flow is a common side-effect of hormonal contraception methods, such as oral contraceptive pills, IUDs that release hormones (such as Mirena), or hormonal implants such as Depo-Provera. The relatively low estrogen contained in most hormonal contraceptives reduces the growth of the endometrium, so there is relatively little endometrium left to be shed during menstruation. Many women find this side-effect to be a benefit of hormonal contraceptive use. Scanty menses or periods can occur normally at the extremes
Hypomenorrhea
2566842
removes the constraint on the physical size of the embryonic mass and exposes the outer cells of the blastocyst to the interior of the uterus. Furthermore, hormonal changes in the mother, specifically a peak in luteinizing hormone (LH), prepare the endometrium to receive and envelop the blastocyst. Once bound to the extracellular matrix of the endometrium, trophoblast cells secrete enzymes and other factors to embed the blastocyst into the uterine wall. The enzymes released degrade the endometrial lining, while autocrine growth factors such as human chorionic gonadotropin (hCG) and insulin-like growth factor (IGF) allow the blastocyst to further invade the
Blastocyst
9270324
it is reflected on to the rectum, forming the recto-uterine pouch. It is in relation with the rectum, from which it may be separated by coils of small intestine. Supravaginal portion of cervix The supravaginal portion of the cervix (also known as the uterine portion of the cervix) is separated in front from the bladder by fibrous tissue (parametrium), which extends also on to its sides and lateralward between the layers of the broad ligaments. The uterine arteries reach the margins of the cervix in this fibrous tissue, while on either side the ureter runs downward and forward in it
Supravaginal portion of cervix
6511821
Luteolysis Luteolysis (also known as luteal regression) is the structural and functional degradation of the corpus luteum (CL), which occurs at the end of the luteal phase of both the estrous and menstrual cycles in the absence of pregnancy. In domestic animals, luteolysis is initiated by the hormones prostaglandin F2alpha and oxytocin. In sheep, communication between the pars nervosa (posterior lobe of the pituitary gland), corpus luteum, and the uterus endometrium via the circulatory system is required for luteolysis. Studies with sheep have found that, if the uterine horn is ipsalateral to the ovary possessing the CL is surgically removed,
Luteolysis
766196
fusion of the underlying cytotrophoblast cells, a process that continues throughout placental development. The syncytiotrophoblast (otherwise known as syncytium), thereby contributes to the barrier function of the placenta. The placenta grows throughout pregnancy. Development of the maternal blood supply to the placenta is complete by the end of the first trimester of pregnancy week 14 (DM). In preparation for implantation of the blastocyst, the uterine endometrium undergoes "decidualisation". Spiral arteries in decidua are remodeled so that they become less convoluted and their diameter is increased. The increased diameter and straighter flow path both act to increase maternal blood flow to
Placenta
11347881
P2RX4 P2X purinoceptor 4 is a protein that in humans is encoded by the "P2RX4" gene. The product of this gene belongs to the family of purinoceptors for ATP. Multiple alternatively spliced transcript variants have been identified for this gene although their full-length natures have not been determined. The receptor is found in the central and peripheral nervous systems, in the epithelia of ducted glands and airways, in the smooth muscle of the bladder, gastrointestinal tract, uterus, and arteries, in uterine endometrium, and in fat cells. P2X receptors have been implicated in the regulation of cardiac function, ATP-mediated cell death,
P2RX4
14600589
Experts are unclear as the condition itself is a rare finding and lack of knowledge presents itself as a challenge. Like the uterine endometrium of Endometriosis, estrogen can cause salpingoitic tissues outside of the fallopian tubes to grow and potentially aggravate the surrounding areas. High levels cause the glandular tissues to proliferate and, especially important, they cause the number of and activity of ciliated epithelial cells (that would normally line the fallopian tubes) to increase. Endosalpingiosis is diagnosed by a pathologist on excision (e.g. biopsy). It is characterized by cysts with tubal-type epithelium (e.g. ciliated epithelium) surrounded by a fibrous
Endosalpingiosis
11135969
P2RX7 P2X purinoceptor 7 is a protein that in humans is encoded by the "P2RX7" gene. The product of this gene belongs to the family of purinoceptors for ATP. Multiple alternatively spliced variants which would encode different isoforms have been identified although some fit nonsense-mediated decay criteria. The receptor is found in the central and peripheral nervous systems, in microglia, in macrophages, in uterine endometrium, and in the retina. The P2X receptor also serves as a pattern recognition receptor for extracellular ATP-mediated apoptotic cell death, regulation of receptor trafficking, mast cell degranulation, and inflammation. The P2X subunits can form homomeric
P2RX7
3940032
ER agonist in bone and the cardiovascular system, but in breast tissue and the endometrium it acts as an ER antagonist. It is extensively metabolized by glucuronide conjugation in the gut and because of that has a low bioavailability of only 2% while that of tamoxifen and toremifene is approximately 100%. The advantage of raloxifene over the triphenylethylene tamoxifen is reduced effect on the uterus. The flexible hinge group, as well as the antiestrogenic phenyl 4-piperidinoethoxy side chain, are important for minimizing uterine effects. Because of its flexibility the side chain can obtain an orthogonal disposition relative to the core
Selective estrogen receptor modulator
9148675
ESCs result in the endometrium developing a secretory lining that produces a variety of proteins, cytokines, and growth factors. These secreted factors will regulate the invasiveness of trophoblast cells that eventually form the placental connection if an embryo implants into the decidua. One of the identifying features of the decidua is the presence of large numbers of leukocytes that are mostly made up of specialized uterine natural killer (uNK) cells and some dendritic cells. As the fetus consists of both maternal and paternal DNA, the decidual leukocytes play a role in suppressing the immune response of the mother to prevent
Decidualization
601464
contribute to increased ovarian stimulation and earlier menopause. Hastened ovarian aging has been observed after endometrial ablation. While it is difficult to prove that these surgeries are causative, it has been hypothesized that the endometrium may be producing endocrine factors contributing to the endocrine feedback and regulation of the ovarian stimulation. Elimination of this factors contributes to faster depletion of the ovarian reserve. Reduced blood supply to the ovaries that may occur as a consequence of hysterectomy and uterine artery embolisation has been hypothesized to contribute to this effect. Impaired DNA repair mechanisms may contribute to earlier depletion of the
Menopause
1932419
semen, it has been detected in other body fluids and tissues. In women, PSA is found in female ejaculate at concentrations roughly equal to that found in male semen. Other than semen and female ejaculate, the greatest concentrations of PSA in biological fluids are detected in breast milk and amniotic fluid. Low concentrations of PSA have been identified in the urethral glands, endometrium, normal breast tissue and salivary gland tissue. PSA also is found in the serum of women with breast, lung, or uterine cancer and in some patients with renal cancer. Tissue samples can be stained for the presence
Prostate-specific antigen
601450
symptoms. During the transition to menopause, menstrual patterns can show shorter cycling (by 2–7 days); longer cycles remain possible. There may be irregular bleeding (lighter, heavier, spotting). Dysfunctional uterine bleeding is often experienced by women approaching menopause due to the hormonal changes that accompany the menopause transition. Spotting or bleeding may simply be related to vaginal atrophy, a benign sore (polyp or lesion), or may be a functional endometrial response. The European Menopause and Andropause Society has released guidelines for assessment of the endometrium, which is usually the main source of spotting or bleeding. In post-menopausal women, however, any genital
Menopause
15696746
ERα and instead activates only ERβ-mediated gene transcription. Menerba has been reported to alleviate menopausal symptoms such as hot flashes, while having no stimulative effects on endometrium or breast tissue. In mouse xenograft models, Menerba produced a different conformation in estrogen receptor alpha (ERα) from ERβ when compared with the conformations produced by estradiol. The specific conformational change induced by Menerba allows ERβ to bind to an estrogen response element and recruit coregulatory proteins that are required for gene activation. It has been shown that the increased risk of breast and uterine cancers is associated with ERα activation and that
Menerba
492030
glycoproteins. Many mature females notice blood clots during menstruation. These appear as clumps of blood that may look like tissue. If there are questions (for example, was there a miscarriage?), examination under a microscope can confirm if it was endometrial tissue or pregnancy tissue (products of conception) that was shed. Sometimes menstrual clots or shed endometrial tissue is incorrectly thought to indicate an early-term miscarriage of an embryo. An enzyme called plasmin – contained in the endometrium – tends to inhibit the blood from clotting. The amount of iron lost in menstrual fluid is relatively small for most women. In
Menstruation
5728937
or folds, that will hold the boar's corkscrew-shaped penis during copulation. Females have bicornuate uteruses and two conceptuses must be present in both uterine horns for pregnancy to be established. Maternal recognition of pregnancy in pigs occurs on days 11 to 12 of pregnancy and is marked by progesterone production from a functioning corpus luteum (CL). To avoid luteolysis by PGF2α, rescuing of the CL must occur via embryonic signaling of estradiol 17β and PGE2. This signaling acts on both the endometrium and luteal tissue to prevent the regression of the CL by activation of genes that are responsible for
Domestic pig
4439249
hyperstimulation, and therefore frozen embryo transfer avails for a separate cycle to focus on optimizing the chances of successful implantation. Children born from vitrified blastocysts have significantly higher birthweight than those born from non-frozen blastocysts. When transferring a frozen-thawed oocyte, the chance of pregnancy is essentially the same whether it is transferred in a natural cycle or one with ovulation induction. In the human, the uterine lining (endometrium) needs to be appropriately prepared so that the embryo(s) can implant. In a natural cycle the embryo transfer takes place in the luteal phase at a time where the lining is appropriately
Embryo transfer
5752859
Stromal cell Stromal cells are connective tissue cells of any organ, for example in the uterine mucosa (endometrium), prostate, bone marrow, lymph node and the ovary. They are cells that support the function of the parenchymal cells of that organ. The most common stromal cells include fibroblasts and pericytes. The interaction between stromal cells and tumor cells is known to play a major role in cancer growth and progression. In addition, by regulating local cytokine networks (e.g. M-CSF, LIF), bone marrow stromal cells have been described to be involved in human haematopoiesis and inflammatory processes. Stromal cells (in the dermis
Stromal cell
12773520
stimulates some of the ova to develop and grow. One ovum is released and it passes through the fallopian tube into the uterus. Hormones produced by the ovaries prepare the uterus to receive the ovum. It sita her and awaits the sperm for fertilization to occur. When this does not occur i.e. no sperm for fertilization, the lining of the uterus, called the endometrium, and unfertilized ova are shed each cycle through the process of menstruation. If the ovum is fertilized by sperm, it attaches to the endometrium and the fetus develops. Most mammal reproductive systems are similar, however, there
Reproductive system
19624072
leiomyomas first published by Wamsteker et al. and then adopted by the European Society of Human Reproduction and Embryology (ESHRE). Added was a category for submucous myomas that make contact with the endometrium but do not distort the endometrial cavity (Type 3), and subclassification for intramural leiomyomas and the various types of subserous myomas. The 2011 publication, as well as other publications authored or coauthored by the FIGO Menstrual Disorders Working Group, also explicitly included the process of investigation – that is, from the identification that a patient actually has one or more symptoms of AUB (FIGO System 1) to
FIGO classification of uterine bleeding
576724
upon entering the uterus, implants in the endometrium, beginning pregnancy. Embryonic implantation not in the uterine wall results in an ectopic pregnancy that can kill the mother. In such animals as rabbits, coitus induces ovulation by stimulating the release of the pituitary hormone gonadotropin; this release greatly increases the likelihood of pregnancy. The term "conception" commonly refers to fertilisation, which is the successful fusion of gametes to form a new organism. Its use 'conception' by some to refer to implantation makes it a subject of semantic arguments about the beginning of pregnancy, typically in the context of the abortion debate.
Fertilisation
19791227
xenoestrogens are suspected to contribute to the development of breast cancer in women and prostate and testicular cancers in men, to reduce male fertility and to interact with the immune system. The gain of the number of human breast cancer cell is biologically identic to the rise, in tissues of the genital tract, of the mitotic activity such as the rodent endometrium. In the 1930s, a new screening test called the uterotrophic bioassay was created, but it was not until 1962 that was firstly normalized by an expert committee. This assay quantifies the addition of uterine wet weight or the
E-SCREEN
7238741
and human chorionic gonadotropin. The invasive lineage creates cytotrophoblasts that are essential in the process of implantation and forming a fully functional placenta. An undifferentiated cytotrophoblastic stem cell will differentiate into an extravillous cytotrophoblast intermediate and then into an interstitial cytotrophoblast. An interstitial cytotrophoblast may then further differentiate into an endovascular cytotrophoblast or form a syncytium. The primary function of an interstitial cytotrophoblast is to anchor the growing fetus to the maternal uterine tissue. These cells may invade the whole endometrium and the proximal third of the myometrium. Once these cells penetrate through the first few layers of cells of
Cytotrophoblast
18875029
portion (orbital part). Some adults have a metopic or frontal suture in the vertical portion. In uterine period in right and left half of frontal region of the fetus there is a membrane tissue. On each half a primary ossification center appears about the end of the second month of the fetus. Primary ossification center extends to form the corresponding half of the vertical part (squama) and horizontal part (orbital part) of the frontal bone. At birth the frontal bone contains two portions, separated by the metopic (frontal) suture. Metopism is the condition of having a persistent metopic suture. Metopic
Metopism
5752861
throughout the body prevents the cancer from invading other organs. Stroma is made up of the non-malignant cells, but can provide an extracellular matrix on which tumor cells can grow. Stromal cells may also limit T-cell proliferation via nitric oxide production, hindering immune capability. Stromal cell Stromal cells are connective tissue cells of any organ, for example in the uterine mucosa (endometrium), prostate, bone marrow, lymph node and the ovary. They are cells that support the function of the parenchymal cells of that organ. The most common stromal cells include fibroblasts and pericytes. The interaction between stromal cells and tumor
Stromal cell
14708373
Metritis Metritis is inflammation of the wall of the uterus, whereas endometritis is inflammation of the functional lining of the uterus, called the endometrium. The term pelvic inflammatory disease (PID) is often used for metritis. Postpartum metritis, also known as puerperal sepsis, occurs within 21 days and is most common within 10 days of delivery. Metritis is characterized by an enlarged uterus and a watery red-brown fluid to viscous off-white purulent uterine discharge, which often has a bad smell. The severity of disease is categorized by the signs of health: Clinical endometritis is defined in cattle as the presence of
Metritis
15918603
Menstruation (mammal) Menstruation in mammals is the shedding of the uterine lining (endometrium). It occurs on a regular basis in sexually reproductive-age females of certain mammal species. Although there is some disagreement in definitions between sources, menstruation is generally considered to be limited to primates. Overt menstruation (where there is bleeding from the uterus through the vagina) is found primarily in humans and close relatives such as chimpanzees. It is common in simians (Old World monkeys, and apes), but completely lacking in strepsirrhine primates and possibly weakly present in tarsiers. Beyond primates, it is known only in bats and the
Menstruation (mammal)
14708377
e91734, .</ref> The word "metritis" ( or ) uses combining forms of "metr-" + "-itis", yielding "uterus inflammation". Metritis Metritis is inflammation of the wall of the uterus, whereas endometritis is inflammation of the functional lining of the uterus, called the endometrium. The term pelvic inflammatory disease (PID) is often used for metritis. Postpartum metritis, also known as puerperal sepsis, occurs within 21 days and is most common within 10 days of delivery. Metritis is characterized by an enlarged uterus and a watery red-brown fluid to viscous off-white purulent uterine discharge, which often has a bad smell. The severity of
Metritis
893748
higher level of substance abuse is due to decreased self-control as a result of the higher metabolic demands during the luteal phase. Infrequent or irregular ovulation is called "oligoovulation". The absence of ovulation is called "anovulation". Normal menstrual flow can occur without ovulation preceding it: an anovulatory cycle. In some cycles, follicular development may start but not be completed; nevertheless, estrogens will be formed and stimulate the uterine lining. Anovulatory flow resulting from a very thick endometrium caused by prolonged, continued high estrogen levels is called "estrogen breakthrough bleeding". Anovulatory bleeding triggered by a sudden drop in estrogen levels is
Menstrual cycle
11121268
this protein can bind BRCA1, as well as regulate the expression of the tumorigenic protein CD44. BRG1 works to activate or repress transcription. Having functional BRG1 is important for development past the pre-implantation stage. Without having a functional BRG1, exhibited with knockout research, the embryo will not hatch out of the zona pellucida, which will inhibit implantation from occurring on the endometrium (uterine wall). BRG1 is also crucial to the development of sperm. During the first stages of meiosis in spermatogenesis there are high levels of BRG1. When BRG1 is genetically damaged, meiosis is stopped in prophase 1, hindering the
SMARCA4
4114133
breakthrough bleeding ceases after one or two cycles. Breakthrough bleeding is most commonly caused by an excessively thick endometrium (uterine lining). This is not a dangerous condition, though the unpredictable and often lengthy periods of bleeding are unpleasant. Breakthrough bleeding may also be caused by hormonal effects of ovulation. Breakthrough bleeding may also itself be a symptom of pregnancy. Breakthrough bleeding is most common when a woman first begins taking oral contraceptives, or changes from one particular oral contraceptive to another, though it is possible for breakthrough bleeding to happen at any time. Smokers are especially prone to breakthrough bleeding
Breakthrough bleeding