Lactation describes the secretion of milk Milk is a translucent white liquid produced by the mammary glands of mammals. It provides the primary source of nutrition for young mammals before they are able to digest other types of food. The early lactation milk is known as colostrum, and carries the mother's antibodies to the baby. It can reduce the risk of many diseases in the baby. The from the mammary glands Mammary glands are the organs that, in mammals, produce milk for the sustenance of the young. These exocrine glands are enlarged and modified sweat glands and give mammals their name. The mammary glands of domestic mammals that have more than two breasts are called dugs, the process of providing that milk to the young, and the period of time that a mother A mother is a woman who has conceived, given birth to, or raised a child in the role of a parent. Because of the complexity and differences of a mothers' social, cultural, and religious definitions and roles, it is challenging to define a mother to suit a universally accepted definition. The masculine equivalent is a father lactates to feed her young. The process occurs in all female Female is the sex of an organism, or a part of an organism, which produces non-mobile ova (egg cells) mammals Mammals are a class of vertebrate, air-breathing animals whose females are characterized by the possession of mammary glands while both males and females are characterized by hair and/or fur, three middle ear bones used in hearing, and a neocortex region in the brain. Some mammals have sweat glands, but most do not, and in humans it is commonly referred to as breastfeeding Breastfeeding is the feeding of an infant or young child with breast milk directly from female human breasts rather than from a baby bottle or other container. Babies have a sucking reflex that enables them to suck and swallow milk. Most mothers can breastfeed for six months or more, without the addition of infant formula or solid food or nursing. In most species milk comes out of the mother's nipples; however, the platypus The Platypus is a semi-aquatic mammal endemic to eastern Australia, including Tasmania. Together with the four species of echidna, it is one of the five extant species of monotremes, the only mammals that lay eggs instead of giving birth to live young. It is the sole living representative of its family (Ornithorhynchidae) and genus ( (a non-placental mammal) releases milk through ducts in its abdomen. In only one species In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are often used, such as similarity of DNA, morphology or of mammal, the Dayak fruit bat The Dayak fruit bat or Dyak fruit bat is a relatively rare frugivorous bat species found only on the Sunda Shelf of southeast Asia, specifically the Malay Peninsula south of the Isthmus of Kra, and the islands of Borneo and Sumatra. There are three species in the genus Dyacopterus: D. spadiceus, D. brooksi and D. rickarti. All are found in the, is milk production a normal male function. In some other mammals, the male may produce milk as the result of a hormone A hormone is a chemical released by a cell in one part of the body, that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. It is essentially a chemical messenger that transports a signal from one cell to another. All multicellular organisms produce hormones; imbalance. This phenomenon may also be observed in newborn infants as well (for instance witch's milk Witch's milk or neonatal milk is milk secreted from the breasts of some newborn infants. It is the result of influence by the mother's hormones before birth. Witch's milk is more likely to be secreted by infants born at full term, and not by prematurely-born infants. Breast milk production occurs in about 5% of newborns and can persist for two).
Galactopoiesis is the maintenance of milk Milk is a translucent white liquid produced by the mammary glands of mammals. It provides the primary source of nutrition for young mammals before they are able to digest other types of food. The early lactation milk is known as colostrum, and carries the mother's antibodies to the baby. It can reduce the risk of many diseases in the baby. The production. This stage requires prolactin Prolactin or Luteotropic hormone (LTH) is a peptide hormone discovered by Dr. Henry Friesen, primarily associated with lactation. In breastfeeding, the act of an infant sucking the nipple stimulates the production of prolactin, which fills the breast with milk via a process called lactogenesis, in preparation for the next feed. Oxytocin, another (PRL) and oxytocin Oxytocin is a mammalian hormone that acts primarily as a neurotransmitter in the brain. Also known as alpha-hypophamine (α–hypophamine), oxytocin has the distinction of being the very first polypeptide hormone to be sequenced and synthesized biochemically by Vincent du Vigneaud et al. in 1953.
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Purpose
The chief function of lactation is to provide nutrition Nutrition is the provision, to cells and organisms, of the materials necessary (in the form of food) to support life. Many common health problems can be prevented or alleviated with a healthy diet and immune protection to the young after birth. In almost all mammals, lactation, or more correctly the suckling stimulus, induces a period of infertility Infertility primarily refers to the biological inability of a person to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term. There are many biological causes of infertility, some which may be bypassed with medical intervention, usually by the suppression of ovulation Ovulation is the process in a female's menstrual cycle by which a mature ovarian follicle ruptures and discharges an ovum . Ovulation also occurs in the estrous cycle of other female mammals, which differs in many fundamental ways from the menstrual cycle. The time immediately surrounding ovulation is referred to as the ovulatory phase or the, which serves to provide the optimal birth spacing for survival of the offspring.[1]
Human lactation
When the baby sucks its mother's breast, a hormone called oxytocin compels the milk to flow from the alveoli, through the ducts (milk canals) into the sacs (milk pools) behind the areola and then into the baby's mouthHormonal influences
From the fourth month of pregnancy Pregnancy is the carrying of one or more offspring, known as a fetus or embryo, inside the womb of a female. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets. Human pregnancy is the most studied of all mammalian pregnancies. Childbirth usually occurs about 38 weeks after conception; i.e., approximately 40 weeks (the second and third trimesters), a woman's body produces hormones A hormone is a chemical released by a cell in one part of the body, that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. It is essentially a chemical messenger that transports a signal from one cell to another. All multicellular organisms produce hormones; that stimulate the growth of the milk duct system in the breasts:
- Progesterone Progesterone also known as P4 is a C-21 steroid hormone involved in the female menstrual cycle, pregnancy (supports gestation) and embryogenesis of humans and other species. Progesterone belongs to a class of hormones called progestogens, and is the major naturally occurring human progestogen—influences the growth in size of alveoli and lobes. Progesterone levels drop after birth. This triggers the onset of copious milk production.[2]
- Oestrogen Estrogens , oestrogens (BE), or œstrogens, are a group of steroid compounds, named for their importance in the estrous cycle, and functioning as the primary female sex hormone, their name comes from estrus/oistros (period of fertility for female mammals) + gen/gonos = to generate—stimulates the milk duct system to grow and become specific. Oestrogen levels also drop at delivery and remain low for the first several months of breastfeeding.[2] It is recommended that breastfeeding mothers avoid oestrogen-based birth control methods, as a spike in estrogen levels may reduce a mother's milk supply.
- Follicle stimulating hormone Follicle-stimulating hormone is a hormone found in humans and other animals. It is synthesized and secreted by gonadotropes of the anterior pituitary gland. FSH regulates the development, growth, pubertal maturation, and reproductive processes of the body. FSH and Luteinizing hormone (LH) act synergistically in reproduction (FSH)
- Luteinizing hormone Luteinizing hormone is a hormone produced by the anterior pituitary gland (LH)
- Prolactin Prolactin or Luteotropic hormone (LTH) is a peptide hormone discovered by Dr. Henry Friesen, primarily associated with lactation. In breastfeeding, the act of an infant sucking the nipple stimulates the production of prolactin, which fills the breast with milk via a process called lactogenesis, in preparation for the next feed. Oxytocin, another—contributes to the increased growth of the alveoli during pregnancy.
- Oxytocin Oxytocin is a mammalian hormone that acts primarily as a neurotransmitter in the brain. Also known as alpha-hypophamine (α–hypophamine), oxytocin has the distinction of being the very first polypeptide hormone to be sequenced and synthesized biochemically by Vincent du Vigneaud et al. in 1953—contracts the smooth muscle Smooth muscle is an involuntary non-striated muscle. It is divided into two sub-groups; the single-unit and multiunit smooth muscle. Within single-unit smooth muscle tissues, the autonomic nervous system innervates a single cell within a sheet or bundle and the action potential is propagated by gap junctions to neighboring cells such that the of the uterus The uterus (from Latin "uterus" , plural uteruses or uteri) or womb is a major female hormone-responsive reproductive sex organ of most mammals including humans. One end, the cervix, opens into the vagina, while the other is connected to one or both fallopian tubes, depending on the species. It is within the uterus that the fetus during and after birth, and during orgasm(s). After birth, oxytocin contracts the smooth muscle layer of band-like cells surrounding the alveoli to squeeze the newly-produced milk into the duct system. Oxytocin is necessary for the milk ejection reflex, or let-down to occur.
- Human placental lactogen (HPL)—From the second month of pregnancy, the placenta The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply. Placentas are a defining characteristic of eutherian or "placental" mammals, but are also found in some snakes and lizards with varying levels of development up to releases large amounts of HPL. This hormone appears to be instrumental in breast, nipple, and areola growth before birth.
By the fifth or sixth month of pregnancy, the breasts are ready to produce milk. It is also possible to induce lactation without pregnancy.
Lactogenesis I
During the latter part of pregnancy, the woman's breasts enter into the Lactogenesis I stage. This is when the breasts make colostrum Colostrum is a form of milk produced by the mammary glands of mammals in late pregnancy. Most species will generate colostrum within one day of giving birth (see below), a thick, sometimes yellowish fluid. At this stage, high levels of progesterone inhibit most milk production. It is not a medical concern if a pregnant woman leaks any colostrum before her baby's birth, nor is it an indication of future milk production.
Lactogenesis II
At birth Childbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus. The process of normal human childbirth is categorized in three stages of labour: the shortening and dilation of the cervix, descent and birth of the infant, and birth of the placenta. In many cases, with, prolactin levels remain high, while the delivery of the placenta results in a sudden drop in progesterone, estrogen, and HPL levels. This abrupt withdrawal of progesterone in the presence of high prolactin levels stimulates the copious milk production of Lactogenesis II.
When the breast is stimulated, prolactin levels in the blood rise, peak in about 45 minutes, and return to the pre-breastfeeding state about three hours later. The release of prolactin triggers the cells in the alveoli to make milk. Prolactin also transfers to the breast milk. Some research indicates that prolactin in milk is greater at times of higher milk production, and lower when breasts are fuller, and that the highest levels tend to occur between 2 a.m. and 6 a.m.[3]
Other hormones—notably insulin, thyroxine, and cortisol—are also involved, but their roles are not yet well understood. Although biochemical markers indicate that Lactogenesis II begins about 30–40 hours after birth, mothers do not typically begin feeling increased breast fullness (the sensation of milk "coming in the breast") until 50–73 hours (2–3 days) after birth.
Colostrum Colostrum is a form of milk produced by the mammary glands of mammals in late pregnancy. Most species will generate colostrum within one day of giving birth is the first milk a breastfed baby receives. It contains higher amounts of white blood cells and antibodies Antibodies are gamma globulin proteins that are found in blood or other bodily fluids of vertebrates, and are used by the immune system to identify and neutralize foreign objects, such as bacteria and viruses. They are typically made of basic structural units—each with two large heavy chains and two small light chains—to form, for example, than mature milk, and is especially high in immunoglobulin A Immunoglobulin A is an antibody that plays a critical role in mucosal immunity. More IgA is produced in mucosal linings than all other types of antibody combined; between 3 and 5g is secreted into the intestinal lumen each day. IgA has two subclasses (IgA1 and IgA2) and can exist in a dimeric form called secretory IgA (sIgA). In its secretory form, (IgA), which coats the lining of the baby's immature intestines, and helps to prevent germs from invading the baby's system. Secretory IgA also helps prevent food allergies.[4] Over the first two weeks after the birth, colostrum production slowly gives way to mature breast milk.[2]
Lactogenesis III
The hormonal endocrine In physiology, the endocrine system is a system of glands, each of which secretes a type of hormone into the bloodstream to regulate the body. The endocrine system is an information signal system like the nervous system. Hormones regulate many functions of an organism, including mood, growth and development, tissue function, and metabolism. The control system drives milk production during pregnancy and the first few days after the birth Postnatal is the period beginning immediately after the birth of a child and extending for about six weeks. Another term would be postpartum period, as it refers to the mother (whereas postnatal refers to the infant). Less frequently used is puerperium. When the milk supply is more firmly established, autocrine Autocrine signaling is a form of signaling in which a cell secretes a hormone or chemical messenger that binds to autocrine receptors on the same cell, leading to changes in the cells. This can be contrasted with paracrine signaling, intracrine signaling, or classical endocrine signaling (or local) control system begins. This stage is called Lactogenesis III
During this stage, the more that milk is removed from the breasts, the more the breast will produce milk.[5][6] Research also suggests that draining the breasts more fully also increases the rate of milk production.[7] Thus the milk supply is strongly influenced by how often the baby feeds and how well it is able to transfer milk from the breast. Low supply can often be traced to:
- not feeding or pumping often enough
- inability of the infant to transfer milk effectively caused by, among other things:
- jaw or mouth structure deficits
- poor latching technique
- rare maternal endocrine disorders
- hypoplastic breast tissue
- a metabolic or digestive inability in the infant, making it unable to digest the milk it receives
- inadequate calorie intake or malnutrition of the mother
Milk ejection reflex
The release of the hormone oxytocin Oxytocin is a mammalian hormone that acts primarily as a neurotransmitter in the brain. Also known as alpha-hypophamine (α–hypophamine), oxytocin has the distinction of being the very first polypeptide hormone to be sequenced and synthesized biochemically by Vincent du Vigneaud et al. in 1953 leads to the milk ejection or let-down reflex. Oxytocin stimulates the muscles surrounding the breast to squeeze out the milk. Breastfeeding mothers describe the sensation differently. Some feel a slight tingling, others feel immense amounts of pressure or slight pain/discomfort, and still others do not feel anything different.
The let-down reflex is not always consistent, especially at first. The thought of breastfeeding or the sound of any baby can stimulate this reflex, causing unwanted leakage, or both breasts may give out milk when an infant is feeding from one breast. However, this and other problems often settle after two weeks of feeding.[citation needed] Stress Stress is a term in psychology and biology, first coined in the 1930s, which has in more recent decades become a commonplace of popular parlance. It refers to the consequence of the failure of an organism – human or animal – to respond appropriately to emotional or physical threats, whether actual or imagined or anxiety can cause difficulties with breastfeeding.
A poor milk ejection reflex can be due to sore or cracked nipples, separation from the infant, a history of breast surgery Surgery is a medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, to help improve bodily function or appearance, and sometimes for religious reasons. An act of performing surgery may be called a surgical procedure, operation, or simply, or tissue damage from prior breast trauma. If a mother has trouble breastfeeding, different methods of assisting the milk ejection reflex may help. These include feeding in a familiar and comfortable location, massage of the breast or back, or warming the breast with a cloth or shower.
Afterpains
The surge of oxytocin that may also possibly trigger the milk ejection reflex also causes the uterus to contract. During breastfeeding, mothers may feel these contractions as afterpains. These may range from period-like cramps to strong labour-like contractions and can be more severe with second and subsequent babies. Some women's breasts also become dry and chapped and even crack open and bleed while breast feeding. Rubbing lanolin on the nipples and areola can help with those problems. Lansinoh HPA Lanolin soothes, heals and protects sore cracked nipples. It is the only topical nipple cream endorsed in the US by La Leche League International*, considered the foremost experts on breastfeeding. [8]
Lactation without pregnancy, Induced lactation, Relactation
Milk production can be obtained "artificially" and intentionally in the absence of pregnancy in the woman. It is not necessary that the woman has been pregnant, and she can even be well into her post-menopausal period. Women who have never been pregnant Pregnancy is the carrying of one or more offspring, known as a fetus or embryo, inside the womb of a female. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets. Human pregnancy is the most studied of all mammalian pregnancies. Childbirth usually occurs about 38 weeks after conception; i.e., approximately 40 weeks are sometimes able to induce enough lactation to breastfeed. This is called "induced lactation". Women who have breastfed before can re-start. This is called "relactation". This is how some adoptive mothers Adoption is a process whereby a person assumes the parenting for another who is not kin and, in so doing, permanently transfers all rights and responsibilities from the original parent or parents. Unlike guardianship or other systems designed for the care of the young, adoption is intended to effect a permanent change in status and as such, usually beginning with a supplemental nursing system or some other form of supplementation, can breastfeed. There is thought to be little or no difference in milk composition whether lactation is artificially induced or a result of pregnancy.[9][10]
Lactation can be induced by physical stimulation and by drugs. In principle—with considerable patience and perseverance—it is possible to induce lactation by sucking on the nipples alone. The nipples may need to be consistently stimulated by a breast pump or actual suckling (several times a day), and the breasts massaged and squeezed ("milked") to encourage the flow of milk.[citation needed] Temporary use of galactagogue A galactagogue is a substance that promotes lactation in humans and other animals. It may be synthetic, plant-derived, or endogenous (milk-inducing) drugs is also effective; galactagogue herbs may also be of use. Once established, lactation responds to demand.
Also, some couples may use lactation for sexual purposes.
Rare accounts of male lactation The phenomenon of male lactation in humans has become more common in recent years due to the use of medications that stimulate a man's mammary glands. The increasing presence of xenoestrogens may also play a role, interfering with the hormonal system of males. In ordinary circumstances, there is so little mammary tissue that it is unnoticeable; if (as distinct from galactorrhea Galactorrhea or galactorrhoea is the spontaneous flow of milk from the breast, unassociated with childbirth or nursing) exist in medical literature.
See also
A 5 day old mouse pup, suckling on an anesthetized, lactating female- Lactation room
- Galactogogue
- Milk line
- Udder An udder is an organ formed of the mammary glands of female quadruped mammals, especially ruminants such as cattle, goats, sheep and deer. The udder is a single mass hanging beneath the animal, consisting of pairs of mammary glands. In cattle there are normally two pairs, in sheep, goats and deer there is one pair, and in some animals such as pigs
Otago Daily Times
Dunedin Hospital lactation consultant Stefanie Kalmakoff said there was a growing awareness of the benefits of breast milk for babies, and it was important ...
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Click to enlarge Breastfeeding and Human Lactation Third Edition is the most current and complete examination of breastfeeding and human
Jessica
Sun, 01 Aug 2010 23:52:00 GM
Well, I read about these cookies called ". Lactation. Cookies", that supposedly help increase your supply. They have oats, almonds, breawer's yeast, and flaxseed meal, among many other yummy ingredients. (Basically, they are oatmeal ...
