Full Answer
What is the purpose of decidualization?
Decidualization. Decidualization is required in some mammalian species where embryo implantation and trophoblast cell invasion of the endometrium occurs, also known as hemochorial placentation. This allows maternal blood to come into direct contact with the fetal chorion, a membrane between the fetal and maternal tissues,...
What is decidualization of endometrium?
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.
What is decidualization in placenta?
Decidualization. It also triggers the production of cellular and molecular factors that result in structural changes, or remodeling, of maternal spiral arteries. Decidualization is required in some mammalian species where embryo implantation and trophoblast cell invasion of the endometrium occurs, also known as hemochorial placentation.
Is decidualization spontaneous?
However, in a handful of species, including humans, Old World monkeys, some bats, elephant shrew, and spiny mouse, decidualization is “spontaneous,” meaning that it is initiated independently of an implanting embryo during the midluteal phase of each cycle ( Emera et al., 2012 ).
What is Decidualized endometrial tissue?
Decidualization refers to the functional and morphological changes that occur within the endometrium to form the decidual lining into which the blastocyst implants. These changes include the recruitment of leukocytes and, importantly, the differentiation of endometrial stromal fibroblast cells (ESCs) into DSCs.
Does decidual reaction mean pregnancy?
Decidual reaction of the cervix is a benign growth produced by the hormones of pregnancy. These reactions or changes in the cervix are present in about 20 per cent of normal pregnant women. They may look like cancer but are not cancer. They are benign lesions.
What causes decidual cells?
OVARIAN STEROID HORMONE CONTROL DECIDUALIZATION Decidualization occurs in response to elevated levels of the ovarian steroid hormones, E2 and progesterone. Hormonal changes are required in order to support the differentiation that is necessary for implantation during the menstrual cycle.
What happens during the decidual reaction?
A decidual reaction is a feature seen in very early pregnancy where there is thickening of the endometrium around the gestational sac, which is seen as an echogenic rim on ultrasound. A thin decidual reaction of <2 mm is considered one of the features suggestive of an anembryonic pregnancy 2.
What is decidual pregnancy?
The decidualization of the inner layer of endometrium, termed decidua, prepares the uterus for pregnancy by permitting trophoblasts invading into it and remodeling of spiral arteries. Decidua plays important roles in embryonic implantation, placentation, and pregnancy maintenance.
What does Decidualized stroma mean?
Decidualized stromal cells are likely highly sensitive sensors of changing hormone levels. This provides a mechanism by which decidualized stromal cells may recruit inflammatory leukocytes into the premenstrual endometrium and contribute to the intense inflammation underlying this unique physiological process.
Does decidual bleeding have cramps?
What are the symptoms of a decidual cast? Before your body expels the decidual cast, you may experience bleeding, spotting, and abdominal pain or menstrual cramps, which may be severe.
Can you shed your uterine lining and still be pregnant?
Your hormone levels during pregnancy will change to prevent you from menstruating, and it is not possible for your body to shed its entire uterine lining while maintaining a pregnancy. It is, however, possible to have menstrual-like bleeding for a variety of reasons during pregnancy.
Where is the decidua?
the uterusThe decidua is the modified mucosal lining of the uterus (that is, modified endometrium) that forms in preparation for pregnancy. It is formed in a process called decidualization under the influence of progesterone.
What is Decidualized gestational sac?
Gestational sac diameter At approximately 4 weeks of menstrual age, a small hypoechoic area appears in the fundus or midportion of the uterus, known as thedouble decidual sac sign. As the sac embeds further into the uterus, it is surrounded by an echogenic rim and is seen within the choriodecidual tissue.
What is poor decidual reaction?
A decidual reaction is a feature seen in very early pregnancy where there is thickening of the endometrium around the gestational sac, which is seen as an echogenic rim on ultrasound. A thin decidual reaction of <2 mm is considered one of the features suggestive of an anembryonic pregnancy 2.
What is the meaning of Anembryonic pregnancy?
A blighted ovum, also called an anembryonic pregnancy, occurs when an early embryo never develops or stops developing, is resorbed and leaves an empty gestational sac. The reason this occurs is often unknown, but it may be due to chromosomal abnormalities in the fertilized egg.
What is decidual tissue?
Abstract. The decidua has been known as maternal uterine tissue, which plays essential roles in protecting the embryo from being attacked by maternal immune cells and provides nutritional support for the developing embryo prior to placenta formation.
What is implantation and decidualization?
Once implantation occurs and the embryo breaches the luminal epithelium, the stromal cells surrounding the implanting embryo transform into a decidua by a process called decidualization [9,95].
Why did I pass a decidual cast?
Decidual cast formation can be associated with ectopic pregnancy or, less commonly, exogenous progesterone. Decidual casts have been attributed to use of oral contraceptives, injectable progesterone, or an implantable progesterone delivery system (Nexplanon).
Is decidua the same as placenta?
The placenta is a fetomaternal organ. The fetal portion of the placenta is known as the villous chorion. The maternal portion is known as the decidua basalis. The two portions are held together by anchoring villi that are anchored to the decidua basalis by the cytotrophoblastic shell.
What causes decidual reaction in pregnancy?
The decidual reaction in the endometrium (and the subsequent formation of the definitive placenta) is induced by mediators released from the blastocyst, although additional support is provided by progesterone produced by the corpora lutea in the ovary.
What is stroma in human body?
(STROH-muh) The cells and tissues that support and give structure to organs, glands, or other tissues in the body. The stroma is mostly made up of connective tissue, blood vessels, lymphatic vessels, and nerves.
What is decidual cast shedding?
Decidual cast shedding (DCS) -- clinically known as membranous dysmenorrhea -- is a rare gynecological event during which the decidua, or the thick mucous membrane that lines the uterus, is shed in full, intact form.
Does a yolk sac confirm pregnancy?
Does a yolk sac confirm pregnancy? The yolk sac is one of the first structures a healthcare provider can see during prenatal ultrasound. It can help confirm pregnancy, along with other factors, such as a missed menstrual cycle and levels of certain hormones in the mother's blood.
What is the meaning of anembryonic pregnancy?
A blighted ovum, also called an anembryonic pregnancy, occurs when an early embryo never develops or stops developing, is resorbed and leaves an empty gestational sac. The reason this occurs is often unknown, but it may be due to chromosomal abnormalities in the fertilized egg.
Can endometrial thickness indicate early pregnancy?
Many studies have found a thin endometrium to be associated with a lower implantation rate, but no absolute cutoff for endometrial thickness exists; good pregnancy rates have been reported in cycles with endometrium <6 mm, and a successful pregnancy has been reported with endometrial thickness of only 4 mm [17].
How long does it take for the gestational sac to form?
The gestational sac is the first structure seen in pregnancy by ultrasound as early as 4.5 to 5 weeks of gestational age, but it is only 97.6% specific for the diagnosis of intrauterine pregnancy.
How does decidualization occur?
By and large, stromal decidualization occurs only in species that undergo interstitial implantation, and the timing and extent of the changes are species-dependent too. In human, decidual changes are evident in the late secretory phase of nonpregnant cycles, and under chronic contraceptive progesterone stimulation, the endometrium becomes fully decidualized. Thus, decidualization can occur independently of embryonic signals. Embryos implant into an undecidualized stroma, with decidualization occurring during the following few days. In contrast, in the mouse and rat, attachment of the embryo to the anti-mesometrial uterine lumenal epithelium initiates a signaling process in steroidally sensitized endometrium that triggers decidualization. Similar changes (known as deciduomata) can be elicited in hormonally sensitized mice, by a mechanical insult to the uterine lumen or by instillation of an irritant such as oil. During days 5–8 of pregnancy, decidual changes spread from the subepithelial anti-mesometrial stroma into deeper anti-mesometrial regions and then spread laterally, eventually including the mesometrial stroma. The anti-mesometrial and mesometrial decidual cells have distinct secretory repertoires.
What is decidualization in embryos?
Decidualization involves the transformation of endometrial stromal fibroblasts into specialized secretory decidual cells that provide a nutritive and immunocompetent matrix indispensable for embryo implantation and placental development (Gellersen and Brosens, 2014).
What changes occur during decidualization?
The changes in morphology associated with decidualization have been studied in detail in laboratory rodents but are thought to be basically similar in most species. The earliest macroscopically identifiable event is an increase in endometrial vascular permeability that results in the development of stromal edema. It is localized to implantation sites but is generalized if an artificial deciduogenic stimulus is applied along the full length of the uterus. The permeability response is followed by an increase in alkaline phosphatase activity. The differentiating stromal cells become enlarged with rounded nuclei. Subsequently, the cells become rounded and typically have two or more polyploid nuclei. Ultrastructurally, the differentiation of decidual cells is characterized by the accumulation of glycogen and lipid droplets and increased amounts of filament proteins. The content of polyribosomes and rough endoplasmic reticulum also increases.
Why are decidual cells important?
As discussed in “ Menstruation ” section in the context of menstruation, decidual cells play an important role in initiating and controlling inflammation in the endometrium. At the same time, immunological management is required to ensure survival of the fetal allograft. This is not achieved by means of wholesale immune suppression, rather immune recognition of the placenta is required, with both local and systemic adjustment of the immunological environment. Trophoblast interaction with the innate immune system via uterine NK cells is one element in this process. Regulatory T cells are also important, indeed mice lacking T regs are infertile. Stromal cell decidualization may therefore have evolved to manage the specific inflammatory and immune processes associated with invasive implantation. In some eutherians, decidual cells are lost after the implantation phase of pregnancy, indicating they are not required for the maintenance of these complex relationships.
What is the process of implantation of an embryo into an undecidualized stroma?
Embryos implant into an undecidualized stroma, with decidualization occurring during the following few days. In contrast, in the mouse and rat, attachment of the embryo to the anti-mesometrial uterine lumenal epithelium initiates a signaling process in steroidally sensitized endometrium that triggers decidualization.
When do decidual cells start to appear?
In women, decidual cells start to appear at the mid-secretory-late secretory transition, about day 23 of the cycle. It is notable therefore that implantation occurs in human before decidual changes have been initiated in the endometrial stroma; though there are few direct observations of these stages, decidualization is probably initiated 1–3 days after trophoblast starts to penetrate the stroma. Decidual cells arise by differentiation of resident stromal cells in response to a prolonged exposure to progesterone, with binding to PRA leading to receptor phosphorylation, dissociation from chaperone proteins, dimerisation, binding to response elements in specific genes, recruitment of coactivators and finally transcription. The resultant chromatin reorganization and genome-wide alteration of histone modification give rise to a profoundly distinct repertoire of gene expression.
Where does decidualization occur in rodents?
In laboratory rodents, in response to either an implanting blastocyst or an artificial stimulus, decidualization begins in the anti-mesometrial pole of the endometrium and, over time, spreads to involve the mesometrial stromal cells. Why this is the case is poorly understood.
What is decidual cast?
Prevention. Outlook. A decidual cast occurs when a large piece of tissue passes through your vaginal canal. Once outside your body, you may notice that it looks like the shape of your uterus. This condition can affect menstruating women. It can cause extreme discomfort as well as vaginal bleeding as it leaves your body.
Why does the decidual cast appear fleshy?
This is because the entire lining exited as one piece. The decidual cast will also appear fleshy because it’s made up of tissue. It’s possible that the decidual cast will also come out in fragments instead of as a single piece of tissue.
How do the symptoms of a decidual cast differ from those of a miscarriage?
The symptoms for miscarriage and decidual cast can be similar. Both can lead to cramping, pain, or vaginal bleeding and the loss of large pieces of tissue. Contact your doctor if you think you might be pregnant and experience these symptoms.
Why does a decidual cast go away?
Generally, symptoms related to this condition go away after the decidual cast exits the body if it’s not related to another condition. There isn’t a single known cause of a decidual cast, but it may be related to hormonal contraception or ectopic pregnancies.
What to ask a doctor before a decidual cast?
Before or after you pass a decidual cast, your doctor may conduct some imaging tests. These can help your doctor diagnose the condition.
Is a decidual cast a side effect?
A decidual cast is rare, and there’s nothing you can do to prevent it. A decidual cast is a possible side effect for some contraceptives. You should be aware of the side effects of any hormonal contraceptives you use.
Can progesterone cause decidual cast?
Hormonal contraceptives, especially those that include a high dose of progesterone, may increase your risk for decidual cast. These may include oral contraceptives as well as those that can be injected or implanted.
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Legalization means that the state has set up a regulatory system that governs the marijuana industry from seed to sale. Companies that grow, transport or sell marijuana must have a license from the state.
Is decriminalizing marijuana a crime?
criminal laws, decriminalize marijuana, legalization vs decriminalization, NORML. Decriminalized marijuana is very different from marijuana legalization. While the moves to decriminalize marijuana vary from state to state, they typically make it no longer a crime to possess small amounts of marijuana, although it may still be confiscated ...
Is marijuana legalized or decriminalized?
Decriminalized marijuana should never be confused with legalization. Legalization allows for the production and sale of either recreational or medical marijuana and marijuana-infused products. Decriminalized marijuana does not allow that but does reduce or eliminate the crime of having a small amount in your possession.
