Human bodyThe human body is the structure of a human being. It is composed of many different types of cells that together create tissues and subsequently organ systems. They ensure homeostasis and the viability of the human body. It comprises a head, hair, neck, torso (which includes the thorax and abdomen), arms and hands, legs and feet. The study of the human body involves anatomy, physiology, histology and embryology. The body varies anatomically in known ways. Physiology focuses on the systems and organs of the human body and their functions.
Estrogen receptorEstrogen receptors (ERs) are a group of proteins found inside cells. They are receptors that are activated by the hormone estrogen (17β-estradiol). Two classes of ER exist: nuclear estrogen receptors (ERα and ERβ), which are members of the nuclear receptor family of intracellular receptors, and membrane estrogen receptors (mERs) (GPER (GPR30), ER-X, and Gq-mER), which are mostly G protein-coupled receptors. This article refers to the former (ER).
LactationLactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process naturally occurs with all sexually mature female mammals, although it may predate mammals. The process of feeding milk in all female creatures is called nursing, and in humans it is also called breastfeeding. Newborn infants often produce some milk from their own breast tissue, known colloquially as witch's milk.
GynecomastiaGynecomastia (also spelled gynaecomastia) 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. Gynecomastia can be normal in newborn male babies due to exposure to estrogen from the mother, in adolescent boys going through puberty, in older men over age 50, and/or in obese men. Most occurrences of gynecomastia do not require diagnostic tests.
BraA bra, short for brassiere or brassière (USbrəˈzɪər, UKˈbræsɪər or ˈbræzɪər; bʁasjɛʁ), is a form-fitting undergarment that is primarily used to support and cover a female's breasts. A typical bra consists of a chest band that wraps around the torso, supporting two breast cups that are held in place by shoulder straps. A bra usually fastens in the back, using a hook and eye fastener, although bras are available in a large range of styles and sizes, including front-fastening and backless designs.
Cleavage (breasts)Cleavage is the narrow depression or hollow between the breasts of a woman. The superior portion of cleavage may be accentuated by clothing such as a low-cut neckline that exposes the division, and often the term is used to describe the low neckline itself, instead of the term décolletage. Joseph Breen, head of the U.S. film industry's Production Code Administration, coined the term in its current meaning when evaluating the 1943 film The Outlaw, starring Jane Russell. The term was explained in Time magazine on August 5, 1946.
Hormone replacement therapyHormone 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. These symptoms can include hot flashes, vaginal atrophy, accelerated skin aging, vaginal dryness, decreased muscle mass, sexual dysfunction, and bone loss or osteoporosis. They are in large part related to the diminished levels of sex hormones that occur during menopause. Estrogens and progestogens are the main hormone drugs used in HRT.
AreolaThe human areola (areola mammae, əˈriːələ or ˌæriˈoʊlə) is the pigmented area on the breast around the nipple. Areola, more generally, is a small circular area on the body with a different histology from the surrounding tissue, or other small circular areas such as an inflamed region of skin. The mature human female nipple has several small openings arranged radially around the tip of the lactiferous ducts from which milk is released during lactation. Other small openings in the areola are sebaceous glands, also known as areolar glands.
MastitisMastitis is inflammation of the breast or udder, usually associated with breastfeeding. Symptoms typically include local pain and redness. There is often an associated fever and general soreness. Onset is typically fairly rapid and usually occurs within the first few months of delivery. Complications can include abscess formation. Risk factors include poor latch, cracked nipples, use of a breast pump, and weaning. The bacteria most commonly involved are Staphylococcus and Streptococci. Diagnosis is typically based on symptoms.
Breast milkBreast milk (sometimes spelled as breastmilk) or mother's milk is milk produced by mammary glands located in the breast of a human female. Breast milk is the primary source of nutrition for newborns, containing fat, protein, carbohydrates (lactose and human milk oligosaccharides) and variable minerals and vitamins. Breast milk also contains substances that help protect an infant against infection and inflammation, whilst also contributing to healthy development of the immune system and gut microbiome.