Estrogen is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal activity: estrone (E1), estradiol (E2), and estriol (E3). Estradiol, an estrane, is the most potent and prevalent. Another estrogen called estetrol (E4) is produced only during pregnancy.
A secondary sex characteristic is a physical characteristic of an organism that is related to or derived from its sex, but not directly part of its reproductive system. In humans, these characteristics typically start to appear during puberty. In animals, they can start to appear at sexual maturity. In humans, secondary sex characteristics include enlarged breasts and widened hips of females, facial hair and Adam's apples on males, and pubic hair on both. In non-human animals, secondary sex characteristics include, for example, the manes of male lions, the bright facial and rump coloration of male mandrills, and horns in many goats and antelopes.
Progesterone (P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the major progestogen in the body. Progesterone has a variety of important functions in the body. It is also a crucial metabolic intermediate in the production of other endogenous steroids, including the sex hormones and the corticosteroids, and plays an important role in brain function as a neurosteroid.
The placenta is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas and waste exchange between the physically separate maternal and fetal circulations, and is an important endocrine organ, producing hormones that regulate both maternal and fetal physiology during pregnancy. The placenta connects to the fetus via the umbilical cord, and on the opposite aspect to the maternal uterus in a species-dependent manner. In humans, a thin layer of maternal decidual (endometrial) tissue comes away with the placenta when it is expelled from the uterus following birth. Placentas are a defining characteristic of placental mammals, but are also found in marsupials and some non-mammals with varying levels of development.
Development of the human body is the process of growth to maturity. The process begins with fertilization, where an egg released from the ovary of a female is penetrated by a sperm cell from a male. The resulting zygote develops through mitosis and cell differentiation, and the resulting embryo then implants in the uterus, where the embryo continues development through a fetal stage until birth. Further growth and development continues after birth, and includes both physical and psychological development that is influenced by genetic, hormonal, environmental and other factors. This continues throughout life: through childhood and adolescence into adulthood.
Estrone (E1), also spelled oestrone, is a steroid, a weak estrogen, and a minor female sex hormone. It is one of three major endogenous estrogens, the others being estradiol and estriol. Estrone, as well as the other estrogens, are synthesized from cholesterol and secreted mainly from the gonads, though they can also be formed from adrenal androgens in adipose tissue. Relative to estradiol, both estrone and estriol have far weaker activity as estrogens. Estrone can be converted into estradiol, and serves mainly as a precursor or metabolic intermediate of estradiol. It is both a precursor and metabolite of estradiol.
Virilization or masculinization is the biological development of adult male characteristics in young males or females. Most of the changes of virilization are produced by androgens.
Bioidentical hormone replacement therapy (BHRT), also known as bioidentical hormone therapy (BHT) or natural hormone therapy, is the use of hormones that are identical on a molecular level with endogenous hormones in hormone replacement therapy. It may also be combined with blood and saliva testing of hormone levels, and the use of pharmacy compounding to obtain hormones in an effort to reach a targeted level of hormones in the body. A number of claims by some proponents of BHT have not been confirmed through scientific testing. Specific hormones used in BHT include estrone, estradiol, progesterone, testosterone, dehydroepiandrosterone (DHEA), and estriol.
Xenoestrogens are a type of xenohormone that imitates estrogen. They can be either synthetic or natural chemical compounds. Synthetic xenoestrogens include some widely used industrial compounds, such as PCBs, BPA, and phthalates, which have estrogenic effects on a living organism even though they differ chemically from the estrogenic substances produced internally by the endocrine system of any organism. Natural xenoestrogens include phytoestrogens which are plant-derived xenoestrogens. Because the primary route of exposure to these compounds is by consumption of phytoestrogenic plants, they are sometimes called "dietary estrogens". Mycoestrogens, estrogenic substances from fungi, are another type of xenoestrogen that are also considered mycotoxins.
An estrogen patch, or oestrogen patch, is a transdermal delivery system for estrogens such as estradiol and ethinylestradiol which can be used in menopausal hormone therapy, feminizing hormone therapy for transgender women, hormonal birth control, and other uses. Transdermal preparations of estrogen are metabolized differently than oral preparations. Transdermal estrogens avoid the first pass through the liver and thus potentially reduce the risk of blood clotting and stroke.
A biopharmaceutical, also known as a biological medical product, or biologic, is any pharmaceutical drug product manufactured in, extracted from, or semisynthesized from biological sources. Different from totally synthesized pharmaceuticals, they include vaccines, whole blood, blood components, allergenics, somatic cells, gene therapies, tissues, recombinant therapeutic protein, and living medicines used in cell therapy. Biologics can be composed of sugars, proteins, nucleic acids, or complex combinations of these substances, or may be living cells or tissues. They are isolated from living sources—human, animal, plant, fungal, or microbial. They can be used in both human and animal medicine.
Hormone replacement therapy (HRT), also known as menopausal hormone therapy or postmenopausal hormone therapy, is a form of hormone therapy used to treat symptoms associated with female menopause. Effects of menopause can include symptoms such as hot flashes, accelerated skin aging, vaginal dryness, decreased muscle mass, and complications such as osteoporosis, sexual dysfunction, and vaginal atrophy. They are mostly caused by low levels of female sex hormones that occur during menopause.
Aromatase deficiency is a rare condition characterized by extremely low levels or complete absence of the enzyme aromatase activity in the body. It is an autosomal recessive disease resulting from various mutations of gene CYP19 (P450arom) which can lead to ambiguous genitalia and delayed puberty in females, continued linear growth into adulthood and osteoporosis in males and virilization in pregnant mothers. As of 2020, fewer than 15 cases have been identified in genetically male individuals and at least 30 cases in genetically female individuals.
Chlormadinone acetate (CMA), sold under the brand names Belara, Gynorelle, Lutéran, and Prostal among others, is a progestin and antiandrogen medication which is used in birth control pills to prevent pregnancy, as a component of menopausal hormone therapy, in the treatment of gynecological disorders, and in the treatment of androgen-dependent conditions like enlarged prostate and prostate cancer in men and acne and hirsutism in women. It is available both at a low dose in combination with an estrogen in birth control pills and, in a few countries like France and Japan, at low, moderate, and high doses alone for various indications. It is taken by mouth.
Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a female, the testicles in a male. In response to the signals, the gonads produce hormones that stimulate libido and the growth, function, and transformation of the brain, bones, muscle, blood, skin, hair, breasts, and sex organs. Physical growth—height and weight—accelerates in the first half of puberty and is completed when an adult body has been developed. Before puberty, the external sex organs, known as primary sexual characteristics, are sex characteristics that distinguish males and females. Puberty leads to sexual dimorphism through the development of the secondary sex characteristics, which further distinguish the sexes.
Gynecomastia is the abnormal non-cancerous enlargement of one or both breasts in males due to the growth of breast tissue as a result of a hormone imbalance between estrogens and androgens. Gynecomastia can cause significant psychological distress or unease.
Li Shizhen's (1597) Bencao gangmu, the classic materia medica of traditional Chinese medicine (TCM), included 35 human drugs, including organs, bodily fluids, and excreta. Crude drugs derived from the human body were commonplace in the early history of medicine. Some of these TCM human drug usages are familiar from alternative medicine, such as medicinal breast milk and urine therapy. Others are uncommon, such as the "mellified man", which was a foreign nostrum allegedly prepared from the mummy of a holy man who only ate honey during his last days and whose corpse had been immersed in honey for 100 years.
Pediatric gynaecology or pediatric gynecology is the medical practice dealing with the health of the vagina, vulva, uterus, and ovaries of infants, children, and adolescents. Its counterpart is pediatric andrology, which deals with medical issues specific to the penis and testes.
Estrogenic substances, also referred to as natural estrogens and sold under the brand name Amniotin among others, is an estrogen medication which was marketed in the 1930s and 1940s and is no longer available. It was a purified extract of animal material such as horse urine, placenta, and/or amniotic fluid, and contained a non-crystalline mixture of estrogens, including estrone, 17β-estradiol, 17α-estradiol, and/or equilin. The medication was thought to contain estrone as its major active ingredient and was described as an estrone-like preparation, or as "essentially estrone". Estrogenic substances was originally produced from the urine of pregnant women, placenta, and/or amniotic fluid, but by the early 1940s, it was manufactured exclusively from the urine of stallions or pregnant mares, similarly to almost all other estrogen preparations on the market.
Animal products in pharmaceuticals play a role as both active and inactive ingredients, the latter including binders, carriers, stabilizers, fillers, and colorants. Animals and their products may also be used in pharmaceutical production without being included in the product itself.
