Physiology of lactation

Lactation is the process of making human milk. Human milk is secreted through your mammary glands, which are located in your breasts. Lactation is hormonally driven and occurs naturally in people who are pregnant. It can also be induced in those who are not pregnant. Lactation will continue as long as milk is being removed from your breasts. Overview Lactation is the process of making human milk. It's driven by hormones and results in milk coming from your nipple. What is lactation? Lactation is the process of producing and releasing milk from the mammary glands in your breasts. Lactation begins in Feeding your baby directly from your breasts is called Where does human milk come from? Human milk comes from your mammary glands inside your • Alveoli: These tiny, grape-like sacs produce and store milk. A cluster of alveoli is called lobules, and each lobule connects to a lobe. • Milk ducts: Each lobe connects to a milk duct. You can have up to 20 lobes, with one milk duct for every lobe. Milk ducts carry milk from the lobules of alveoli to your nipples. • Areola: The dark area surrounding your nipple, which has sensitive nerve endings that lets your body know when to release milk. To release milk, the entire areola needs stimulation. • Nipple: Your nipple contains several tiny pores (up to about 20) that secrete milk. Nerves on your nipple respond to suckling (either by a baby, your hands or a breast pump). This stimulation tells your brain to release milk from the alveoli th...

Study Assessment Option By completing 4 multiple-choice questions (randomly selected) after studying this chapter readers can qualify for Continuing Professional Development awards from FIGO plus a Study Completion Certificate from GLOWM See end of chapter for details INTRODUCTION AND SCOPE The postpartum period commences after birth of the baby, and marks the end of pregnancy. The puerperium is the period of about 6 weeks, when we give special attention to the changes occurring in the mother’s body. These changes primarily include the return of the maternal organs to around pre-pregnant sizes and functions, endocrine changes as the placenta is lost, and the onset of lactation. Thought should be given early in the puerperium about contraception, and when to resume sexual relations. Local cultural or religious traditions can affect how new mothers are expected to behave in this period, but do not interfere with the normal course of the physiological events we are considering. There are particular risks associated with the puerperal period, especially infection, hemorrhage and psychosis, which speaks to the need for continued healthcare, education and help, even when pregnancy has ended with the delivery of a healthy baby. Our goal is to give an overview of the physiological puerperal changes, and highlight any new understandings. We first discuss changes to the reproductive tract and other organs, and then the cardiovascular and endocrine systems. Maternal physical and ment...

Lactation Physiology Much of lactation physiology in the human has been based on research done in the bovine and other mammals. From: Breastfeeding (Ninth Edition), 2022 Related terms: • Parathyroid Hormone-Related Protein • Human Milk • Lactation • Breastfeeding • Childbirth • Milk Production • Prematurity • Prolactin Ruth A. Lawrence, in Breastfeeding (Ninth Edition), 2022 Understanding the Myth of “MILK COMING IN” Much of lactation physiology in the human has been based on research done in the bovine and other mammals. This has led to some misinterpretation of human data. An important understanding is that despite the tendencies of other species, human secretory activation occurs after parturition rather than before. Only a small volume of colostrum is available during the first 24 to 48hours after birth. Today, in newborn nurseries, fixation on technology and measurements has led to the determination of blood sugars and strict attention to the newborn’s intake. Human newborns are born with significant stores of energy in body fat and mobilize adequate energy from these sources. This represents colostrum already secreted in the ducts and not the rapid synthesis and secretion of milk. Thus, the awaiting of milk “coming in” has been reported in the first 96hours. Many women do not experience a sudden change but a gradual one. When the timing of “milk coming in” is compared with the actual physiologic measurements of the increase in lactose and the decrease in sodium, it i...

\( \newcommand\) • • • • • • Lactation is the secretion of milk from specialized glands (mammary glands) to provide nourishment to offspring. Key Points • Lactation is a hallmark feature of female mammals. • Lactation is under endocrine control. The two main hormones involved are prolactin and oxytocin. • Lactogenesis, or the process of changes to the mammary glands to begin producing milk, begins during the late stages of pregnancy. The delivery of the placenta and the resulting dramatic reduction in progesterone, estrogen, and human placental lactogen levels stimulate milk production. • Colostrum is the first milk a breastfed baby receives. It contains higher amounts of white blood cells and antibodies than mature milk and is especially high in immunoglobulin A. This immunoglobulin coats the lining of the baby’s immature intestines, helping to prevent pathogens from invading the baby’s system. Key Terms • witch’s milk: Witch’s milk or neonatal milk is milk secreted from the breasts of some newborn human infants of either sex. Neonatal milk secretion is considered a normal physiological occurrence and no treatment or testing is necessary. • mammary gland: A gland that secretes milk for suckling an infant or offspring. • lactation: 1. The secretion of milk from the mammary gland of a female mammal. 2. The process of providing the milk to the young, such as breastfeeding. 3. The period of time that a mother lactates to feed her young; the lactation period. • human placental...