|Systematic (IUPAC) name|
|Mol. mass||272. IUPAC Nomenclature is a system of naming Chemical compounds and of describing the science of Chemistry in general CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to The Anatomical Therapeutic Chemical Classification System is used for the classification of drugs It is controlled by the WHO Collaborating Centre for Drug A section of the Anatomical Therapeutic Chemical Classification System. PubChem is a Database of chemical Molecules The system is maintained by the National Center for Biotechnology Information (NCBI a component A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the The molecular mass (abbreviated m of a substance, more commonly referred to as molecular weight and abbreviated as MW, is the Mass of one 39|
|Bioavailability||97-99% is bound|
|Half life||~ 13 hours|
S4 (Au), POM (UK), ℞-only (U. In Pharmacology, bioavailability is used to describe the fraction of an administered Dose of unchanged drug that reaches the Systemic circulation, one of Drug metabolism is the Metabolism of drugs, their Biochemical modification or degradation usually through specialized enzymatic systems The liver is a vital organ in the human body and is present in Vertebrates and some other animals The biological half-life of a substance is the time it takes for a substance (drug radioactive nuclide or other to lose half of its pharmacologic physiologic or radiologic activity Excretion is the process of eliminating waste products of Metabolism and other non-useful materials The pregnancy category of a pharmaceutical agent is an assessment of the risk of fetal injury due to the pharmaceutical if it is used as directed by the mother during The United States of America —commonly referred to as the The regulation of therapeutic goods, that is drugs and therapeutic devices, varies by jurisdiction The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located S. )
Estradiol (17β-estradiol) (also oestradiol) is a sex hormone. In Pharmacology and Toxicology, a route Sex steroids, also known as gonadal steroids, are Steroid hormones that interact with Vertebrate Androgen or Estrogen receptors Mislabelled the "female" hormone, it is also present in males; it represents the major estrogen in humans. Estrogens (US otherwise oestrogens or œstrogens) are a group of Steroid compounds named for their importance in the Estrous cycle, Estradiol has not only a critical impact on reproductive and sexual functioning, but also affects other organs including bone structure.
Estradiol, like other steroids, is derived from cholesterol. A steroid is a Terpenoid Lipid characterized by a Carbon skeleton with four fused rings generally arranged in a 6-6-6-5 fashion Cholesterol is a Lipid found in the Cell membranes and transported in the Blood plasma of all Animals It is an essential component of mammalian After side chain cleavage and utilizing the delta-5 pathway or the delta-4 pathway androstenedione is the key intermediary. A side chain in Organic chemistry and Biochemistry is a part of a Molecule that is attached to a core structure Androstenedione (also known as 4-androstenedione) is a 19- Carbon Steroid Hormone produced in the Adrenal glands and the Gonads A fraction of the androstenedione is converted to testosterone, which in turn undergoes conversion to estradiol by an enzyme called aromatase. Androstenedione (also known as 4-androstenedione) is a 19- Carbon Steroid Hormone produced in the Adrenal glands and the Gonads Testosterone is a Steroid hormone from the Androgen group In mammals testosterone is primarily secreted in the testes of males and the Ovaries Alternatively, androstenedione is "aromatized" to estrone, which is subsequently converted to estradiol. Androstenedione (also known as 4-androstenedione) is a 19- Carbon Steroid Hormone produced in the Adrenal glands and the Gonads Estrone (also oestrone) is an Estrogenic Hormone secreted by the Ovary.
During the reproductive years, most estradiol in women is produced by the granulosa cells of the ovaries by the aromatization of androstenedione (produced in the theca folliculi cells) to estrone, followed by conversion of estrone to estradiol by 17β-hydroxysteroid reductase. A granulosa cell is a Somatic cell found closely associated with the developing female Gamete (called an Oocyte or egg "Ovaria" redirects here This is also a proposed section and a Synonym of Solanum. The theca folliculi comprise a layer of the Ovarian follicles They appear as the follicles become Tertiary follicles The theca are divided into two layers the Estrone (also oestrone) is an Estrogenic Hormone secreted by the Ovary. Smaller amounts of estradiol are also produced by the adrenal cortex, and (in men), by the testes. Situated along the perimeter of the Adrenal gland, the adrenal cortex mediates the stress response through the production of Mineralocorticoids and Glucocorticoids The testicle (from Latin testiculus, diminutive of testis, meaning "witness" virility plural testes) is the male
Estradiol is not only produced in the gonads: in both sexes, precursor hormones, specifically testosterone, are converted by aromatization to estradiol. In particular, fat cells are active to convert precursors to estradiol, and will continue to do so even after menopause. "Adipose" redirects here For the Doctor Who monster see " Partners in Crime " Estradiol is also produced in the brain and in arterial walls. Arteries are Blood vessels that carry blood away from the Heart.
Estradiol enters cells freely and interacts with a cytoplasmic target cell receptor. In Biochemistry, a receptor is a Protein molecule embedded in either the Plasma membrane or Cytoplasm of a cell to which a mobile signaling When the estrogen receptor has bound its ligand it can enter the nucleus of the target cell, and regulate gene transcription which leads to formation of messenger RNA. The estrogen receptor (ER is a member of the nuclear hormone family of Intracellular receptors which is activated by the Hormone 17β-estradiol In Chemistry, a ligand is either an Atom, Ion, or Molecule (see also Functional group) that bonds to a central metal generally In Cell biology, the nucleus (pl nuclei; from Latin la ''nucleus'' or la ''nuculeus'' "little nut" or kernel is a membrane-enclosed Transcription is the synthesis of RNA under the direction of DNA Messenger ribonucleic acid ( mRNA) is a molecule of RNA encoding a chemical "blueprint" for a Protein product The mRNA interacts with ribosomes to produce specific proteins that express the effect of estradiol upon the target cell. Ribosomes ( from ribo nucleic acid and "Greek soma ( meaning body") are complexes of RNA and Protein that
Estradiol binds well to both estrogen receptors, ERα and ERβ, in contrast to certain other estrogens, notably medications that preferentially act on one of these receptors. These medications are called selective estrogen receptor modulators, or SERMs. Selective Estrogen Receptor Modulators ( SERMs) are a class of Medication that acts on the Estrogen receptor.
Estradiol is the most potent naturally-occurring estrogen.
Recently there has been speculation about a membrane estrogen receptor, ERX.
In plasma, estradiol is largely bound to sex hormone binding globulin, also to albumin, -only a fraction is free and biologically active. Sex hormone-binding globulin ( SHBG) is a Glycoprotein that binds to Sex hormones, specifically Testosterone and Estradiol. Albumin (Latin albus white refers generally to any Protein with water Solubility, which is moderately soluble in concentrated salt solutions and experiences Deactivation includes conversion to less active estrogens such as estrone and estriol. Estrone (also oestrone) is an Estrogenic Hormone secreted by the Ovary. Estriol (also oestriol) is one of the three main Estrogens produced by the human body Estriol is the major urinary metabolite. Estradiol is conjugated in the liver by sulfate and glucuronide formation and as such excreted via the kidneys. Some of the watersoluble conjugates are excreted via the bile duct, and partly reabsorbed after hydrolysis from the intestinal tract. Hydrolysis is a Chemical reaction during which one or more water molecules are split into hydrogen and hydroxide ions which may go on to participate in further reactions This enterohepatic circulation contributes to maintaining estradiol levels. Enterohepatic circulation refers to the circulation of Bile from the Liver, where it is produced to the Small intestine, where it aids in Digestion
Serum estradiol measurement in women reflects primarily the activity of the ovaries. As such they are useful in the detection of baseline estrogen in women with amenorrhea or menstrual dysfunction and to detect the state of hypoestrogenicity and menopause. Amenorrhoea ( BE) amenorrhea ( AmE) or amenorrhœa, is the absence of a Menstrual period in a woman of reproductive age Menopause is the permanent shutting down of the female Reproductive system, a considerable length of time before the end of the lifespan Furthermore, estrogen monitoring during fertility therapy assesses follicular growth and is useful in monitoring the treatment. Estrogen-producing tumors will demonstrate persistent high levels of estradiol and other estrogens. In precocious puberty estradiol levels are inappropriately increased. Precocious puberty (La pubertas praecox) is an unusually early onset of Puberty, the process of sexual maturation triggered by the brain or exogenous chemicals which
In the normal menstrual cycle estradiol levels measure typically <50 ng/ml at menstruation, rise with follicular development, drop briefly at ovulation, and rise again during the luteal phase for a second peak. The menstrual cycle is a recurring cycle of physiologic changes that occurs in reproductive-age Females Overt menstruation (where there is blood flow from the At the end of the luteal phase estradiol levels drop to their menstrual levels unless there is a pregnancy.
During pregnancy estrogen levels including estradiol rise steadily towards term. Pregnancy ( Latin graviditas) is the carrying of one or more offspring known as a Fetus or Embryo, inside the Uterus of a Female The source of these estrogens is the placenta that aromatizes prohormones produced in the fetal adrenal gland. The placenta is an Ephemeral organ present in placental Vertebrates, such as Eutherial Mammals and Sharks during Gestation
In the female, estradiol acts as a growth hormone for tissue of the reproductive organs, supporting the lining of the vagina, the cervical glands, the endometrium and the lining of the fallopian tubes. The vagina (from Latin, literally " Sheath " or " Scabbard " is a fibromuscular tubular tract leading from the Uterus The endometrium is the inner membrane of the Mammalian Uterus. It enhances growth of the myometrium. The myometrium is the middle layer of the uterine wall consisting of smooth muscle cells and supporting stromal and vascular tissue Estradiol appears necessary to maintain oocytes in the ovary. An oocyte, ovocyte, or rarely ocyte, is a female Gametocyte or Germ cell involved in reproduction. "Ovaria" redirects here This is also a proposed section and a Synonym of Solanum. During the menstrual cycle, estradiol that is produced by the growing follicle triggers, via a positive feedback system, the hypothalamic-pituitary events that lead to the luteinizing hormone surge, inducing ovulation. The menstrual cycle is a recurring cycle of physiologic changes that occurs in reproductive-age Females Overt menstruation (where there is blood flow from the Luteinizing hormone ( LH, also known as lutropin) is a Hormone produced by the Anterior pituitary gland. In the luteal phase estradiol, in conjunction with progesterone, prepares the endometrium for implantation. Progesterone is a C-21 Steroid Hormone involved in the Female Menstrual cycle, Pregnancy (supports Gestation Implantation is an event that occurs early in pregnancy in which the Embryo adheres to the wall of Uterus. During pregnancy estradiol increases due to placental production. Pregnancy ( Latin graviditas) is the carrying of one or more offspring known as a Fetus or Embryo, inside the Uterus of a Female The placenta is an Ephemeral organ present in placental Vertebrates, such as Eutherial Mammals and Sharks during Gestation In baboons, blocking of estrogen production leads to pregnancy loss suggesting that estradiol has a role in the maintenance of pregnancy. Research is investigating the role of estrogens in the process of initiation of labor. Childbirth (also called labour, birth, partus or parturition) is the culmination of a Human Pregnancy or
The development of secondary sex characteristics in women is driven by estrogens, specifically estradiol. Secondary sex characteristics are traits that distinguish the two Sexes of a species but that are not directly part of the Reproductive system. These changes are initiated at the time of puberty, most enhanced during the reproductive years, and become less pronounced with declining estradiol support after the menopause. Thus, estradiol enhances breast development, and is responsible for changes in the body shape affecting bones, joints, fat deposition. Fat structure and skin composition are modified by estradiol.
The effect of estradiol (and estrogens) upon male reproduction is complex. Estradiol is produced in the Sertoli cells of the testes. A Sertoli cell (a kind of Sustentacular cell) is a 'nurse' cell of the testes which is part of a Seminiferous tubule. There is evidence that estradiol is to prevent apoptosis of male germ cells. 
Several studies have noted that sperm counts have been declining in many parts of the world and it has been postulated that this may be related to estrogen exposure in the environment. A semen analysis evaluates certain characteristics of a man's Semen and the sperm contained in the semen  Suppression of estradiol production in a subpopulation of subfertile men may improve the semen analysis. 
Males with sex chromosome genetic conditions such as Klinefelters Syndrome will have a higher level of estradiol. Klinefelter's syndrome, 47XXY or XXY syndrome is a condition caused by a Chromosome Aneuploidy.
There is ample evidence that estradiol has a profound effect on bone. Individuals without estradiol (or other estrogens) will become tall and eunuchoid as epiphysieal closure is delayed or may not take place. Bone structure is affected resulting in early osteopenia and osteoporosis.  Also, women past menopause experience an accelerated loss of bone mass due to a relative estrogen deficiency.
Estradiol has complex effects on the liver. It can lead to cholestasis. In Medicine, cholestasis is a condition where Bile cannot flow from the Liver to the Duodenum. It affects the production of multiple proteins including lipoproteins, binding proteins, and proteins responsible for blood clotting. A lipoprotein is a biochemical assembly that contains both Proteins and Lipids The lipids or their derivatives may be covalently or non-covalently bound Coagulation is a complex process by which Blood forms Clots It is an important part of Hemostasis (the cessation of blood loss from a damaged vessel whereby
Estrogens can be produced in the brain from steroid precursors. As antioxidants, they have been found to have neuroprotective function. An antioxidant is a Molecule capable of slowing or preventing the oxidation of other molecules 
The positive and negative feedback loop of the menstrual cycle involve ovarian estradiol as the link to the hypothalamic-pituitary system to regulate gonadotropins. Feedback is a circular causal Process whereby some proportion of a system's output is returned (fed back to the Input. The menstrual cycle is a recurring cycle of physiologic changes that occurs in reproductive-age Females Overt menstruation (where there is blood flow from the Gonadotropins are Protein Hormones secreted by Gonadotrope cells of the Pituitary gland of Vertebrates Gonadotropin is sometimes
Estrogen is considered to play a significant role in women’s mental health. A conceptual model of how estrogen affects mood was suggested by Douma et al 2005 based on their extensive literature review relating activity of endogenous, bio-identical and synthetic estrogen with mood and well-being. They concluded that the sudden estrogen withdrawal, fluctuating estrogen, and periods of sustained estrogen low levels correlated with significant mood lowering. Clinical recovery from depression postpartum, perimenopause, and postmenopause was shown to be affective after levels of estrogen were stabilized and/or restored. 
Estrogen is suspected to activate certain oncogenes, as it supports certain cancers, notably breast cancer and cancer of the uterine lining. An oncogene is a protein encoding Gene, which — when deregulated — participates in the onset and development of Cancer. Breast cancer is a Cancer that starts in the cells of the Breast in women and men The endometrium is the inner membrane of the Mammalian Uterus. In addition there are several benign gynecologic conditions that are dependent on estrogen such as endometriosis, leiomyomata uteri, and uterine bleeding. Endometriosis (from endo, "inside" and metra, " Womb " is a common medical condition characterized by growth beyond or outside the uterus A leiomyoma (plural is 'leiomyomata' is a Benign Smooth muscle Neoplasm that is not Premalignant.
The effect of estradiol, together with estrone and estriol, in pregnancy is less clear. Pregnancy ( Latin graviditas) is the carrying of one or more offspring known as a Fetus or Embryo, inside the Uterus of a Female They may promote uterine blood flow, myometrial growth, sitmulate breast growth and at term, promote cervical softening and expression of myometrial oxytocin receptors.
One of the fascinating twists to mammalian sex differentiation is that estradiol is one of the two active metabolites of testosterone in males (the other being dihydrotestosterone), and since fetuses of both sexes are exposed to similarly high levels of maternal estradiol, this source cannot have a significant impact on prenatal sex differentiation. See Sex differences in humans for permanent sex differences Sexual differentiation is the process of development of the differences between Dihydrotestosterone ( DHT) (Full name 5α-Dihydrotestosterone, abbreviating to 5α-DHT; INN: androstanolone; commonly called Estradiol cannot be transferred readily from the circulation into the brain, while testosterone can, thus sex differentiation can be caused by the testosterone in the brain of most male mammals, including humans, aromatizing in significant amounts into estradiol. There is also now evidence that the programming of adult male sexual behavior in animals is largely dependent on estradiol produced in the central nervous system during prenatal life and early infancy from testosterone.  However, it is not yet known whether this process plays a minimal or significant part in human sexual behaviors although evidence from other mammals tends to indicate that it does. 
Recently, it was discovered that volumes of sexually dimorphic brain structures in phenotypical males changed to approximate those of typical female brain structures when exposed to estradiol over a period of months. Sexual dimorphism is the systematic difference in form between individuals of different Sex in the same Species.  This would suggest that estradiol has a significant part to play in sex differentiation of the brain, both pre-natal and throughout life.
Estrogen is marketed in a number of ways to address issues of hypoestrogenism. Hypoestrogenism refers to a lower than normal level of Estrogen. Thus there are oral, transdermal, topical, injectable, and vaginal preparations. Furthermore, the estradiol molecule may be linked to an alkyl group at C3 position to facilitate the administration. An alkyl is a Univalent radical consisting of Carbon and Hydrogen atoms arranged in a chain Such modifications give rise to estradiol acetate (oral and vaginal applications) and to estradiol cyprionate (injectable).
Oral preparations are not necessarily predictably absorbed and subject to a first pass through the liver where they can be metabolized and also initiate unwanted side effects. Thus, alternative routes of administration have been developed that bypass the liver before primary target organs are hit. Transdermal and transvaginal routes are not subject to the initial liver passage.
If severe side effects of low levels of estradiol in a woman's blood are experienced (commonly at the beginning of menopause or after oophorectomy), hormone replacement therapy may be prescribed. Ethinylestradiol, also ethinyl estradiol (EE is a Derivative of Estradiol. Menopause is the permanent shutting down of the female Reproductive system, a considerable length of time before the end of the lifespan Oophorectomy (or ovariectomy) is the surgical removal of an Ovary or ovaries Hormone replacement therapy may refer to Hormone replacement therapy (menopause Hormone replacement therapy (female-to-male Often such therapy is combined with a progestin. A progestin is a synthetic progestagen that has progestinic effects similar to Progesterone.
Estrogen therapy may be used in treatment of infertility in women when there is a need to develop sperm-friendly cervical mucus or an appropriate uterine lining. Female infertility|Male infertility Infertility primarily refers to the biological inability of a Man or a Woman to contribute to conception. The cervix (from Latin "neck" is the lower narrow portion of the Uterus where it joins with the top end of the Vagina.
Estrogen therapy is also used to maintain female hormone levels in male-to-female transsexuals. A transwoman (also spelled trans woman or trans-woman) is a male-to-female transsexual and the term transwoman is preferred by many such
Estrogen is considered to play a significant role in women’s mental health. A conceptual model of how estrogen affects mood was suggested by Douma et al 2005 based on their extensive literature review relating activity of endogenous, bio-identical and synthetic estrogen with mood and well-being. They concluded the sudden estrogen withdrawal, fluctuating estrogen, and periods of sustained estrogen low levels correlated with significant mood lowering. Clinical recovery from depression postpartum, perimenopause, and postmenopause was shown to be affective after levels of estrogen were stabilized and/or restored.
Inducing a state of hypoestrogenism may be beneficial in certain situations where estrogens are contributing to unwanted effects, e. g, certain forms of breast cancer, gynecomastia, and premature closure of epiphyses. Breast cancer is a Cancer that starts in the cells of the Breast in women and men Gynecomastia, or gynaecomastia, ˌgaɪnəkoʊˈmæstiə is the development of abnormally large Mammary glands in Males resulting in breast enlargement which Bone age is a way of describing the degree of maturation of a child's Bones As a person grows from fetal life through childhood Puberty, and finishes growth Estrogen levels can be reduced by inhibiting production using gonadotropin- releasing factor agonists (GnRH agonists) or blocking the aromatase enzyme using an aromatase inhibitor, or estrogen effects can be reduced with estrogen antagonists such as tamoxifen. A gonadotropin-releasing hormone agonist ( GnRH agonist) is a synthetic Peptide modeled after the hypothalamic Neurohormone GnRH that interacts Aromatase inhibitors ( AI) are a class of drugs used in the treatment of Breast cancer and Ovarian cancer in postmenopausal women that Tamoxifen is an orally active Selective estrogen receptor modulator (SERM that is used in the treatment of Breast cancer and is currently the world's largest Flaxseed is known to reduce estradiol. 
A synthetic form of estradiol, called ethinylestradiol is a major component of hormonal contraceptive devices. Ethinylestradiol, also ethinyl estradiol (EE is a Derivative of Estradiol. Combined forms of hormonal contraception contain ethinylestradiol and a progestin, which both contribute to the inhibition of GnRH, LH, and FSH. Hormonal contraception refers to Birth control methods that act on the hormonal system Ethinylestradiol, also ethinyl estradiol (EE is a Derivative of Estradiol. A progestin is a synthetic progestagen that has progestinic effects similar to Progesterone. Gonadotropin-releasing hormone ( GNRH) also known as Luteinizing-hormone releasing hormone ( LHRH) is a tropic Peptide Hormone Luteinizing hormone ( LH, also known as lutropin) is a Hormone produced by the Anterior pituitary gland. The inhibition of these hormones accounts for the ability of these birth control methods to prevent ovulation and thus prevent pregnancy. Hormones (from Greek ὁρμή - "impetus" are chemicals released by cells that affect cells in other parts of the body Birth control, sometimes synonymous with contraception, is a regimen of one or more actions devices or Medications followed in order to deliberately prevent Other types of hormonal birth control contain only progestins and no ethinylestradiol. A progestin is a synthetic progestagen that has progestinic effects similar to Progesterone. Ethinylestradiol, also ethinyl estradiol (EE is a Derivative of Estradiol.
The following are marketed versions of estradiol:
Estradiol is also part of conjugated estrogen preparations, including Premarin but is not the major ingredient (Premarin consists of hundreds of estrogen derivatives due to its natural source. Premarin is the commercial name for compound drug consisting primarily of conjugated Estrogens Isolated from mare's Urine ( PRE gnant . . pregnant mare urine.
Estradiol should not be given to women who are pregnant or are breastfeeding, women with unexplained uterine bleeding, certain forms of cancer, or prone to blood clotting disorders. The medication is to be kept away from children. Detailed prescription information is available 
Side effects of estradiol therapy may include uterine bleeding, breast tenderness, nausea and vomiting, chloasma, cholestasis, and migraine headaches. Melasma (also known as chloasma or the mask of pregnancy when present in pregnant women) is a tan or dark facial skin discoloration Migraine is a neurological Syndrome characterized by altered bodily experiences painful headaches and nausea