Lactation


Lactation

Lactation

Definition

Lactation refers to the formation of milk in the breasts during the period following childbirth . Breastfeeding is the process of the infant obtaining milk by suckling at the breast.

Description

Although breast development begins around puberty , development of mammary function is only completed in pregnancy. During the first half of pregnancy the mammary ducts proliferate and group together to form large lobules. During the second half of pregnancy, secretory activity increases and the alveoli become distended by accumulating colostrum. After 16 weeks of pregnancy, lactation occurs even if the pregnancy does not progress.

The ability of the mammary gland to secrete milk during later pregnancy is called lactogenesis, stage 1. During this time, breast size increases and fat droplets accumulate in the secretory cells. The onset of copious milk secretions after birth is lactogenesis, stage 2, and usually occurs from day two or three to eight days postpartum. During this time, the milk goes through a maturation process to match the infant's needs. Without the hormone prolactin, lactation would not occur. During pregnancy prolactin helps to increase breast mass but does not cause lactation because it is inhibited by the hormone progesterone, which is made by the placenta. The inhibiting influence of progesterone is so strong that lactation is delayed if any of the placenta is retained after birth. Prolactin levels rise and fall in direct proportion to the frequency, intensity, and duration of nipple stimulation from the infant's suckling. During the first week after birth, prolactin levels in breastfeeding women fall about 50 percent. If a mother does not breastfeed, prolactin levels usually reach the levels of the nonpregnant state by seven days postpartum. After milk "comes in" or rapidly increases in volume, lactation is no longer driven by the hormone prolactin. It shifts control to a milk removal driven process, i.e., sucking stimulus. Thus, the initiation of lactation is not driven by breastfeeding, but breastfeeding is necessary for the continuation of lactation.

The breast is not a passive container of milk. It is an organ that actively produces milk due to the stimulus of the infant's sucking; the removal of milk from the breasts causes continued milk production. It is a supply and demand response that regulates the production of milk to match the intake of the infant. The composition of breast milk changes to meet the specific needs of the growing infant. In response to suckling, the hormone oxytocin causes the milk ejection reflex or "let-down" reflex to occur. Milk ejection is the forceful expulsion of milk from the alveoli openings. Oxytocin secretion is also nature's way of causing a woman's uterus to contract after birth to control postpartum bleeding and assist in uterine involution. These contractions can continue for up to 20 minutes after feeding and may be painful during the first few days. The benefit of this, however, is that uterine discharge diminishes faster and the uterine involution occurs more quickly.

Colostrum is thick and creamy yellow as compared with mature milk, which is thin and bluish-white. Compared with mature milk, colostrum is richer in protein and minerals and lower in carbohydrates, fat, and some vitamins . The high concentration of total protein and minerals in colostrum gradually changes to meet the infant's needs over the first two to three weeks until lactation is established. The key component in colostrum and breast milk is immunoglobulins or antibodies that serve to protect the infant against infections or viruses. Breast milk also facilitates the development of the infant's own immune system to mature faster. As a result, breast-fed babies have fewer ear infections, diarrhea , rashes , allergies , and other medical problems than bottle-fed babies. Human milk is rich in proteins, lipids, carbohydrates, vitamins, minerals, hormones, enzymes, growth factors, and many types of protective agents. It contains about 10 percent solids for energy and growth and the rest is water, which is essential to maintain hydration. This is also why a breastfed baby does not need additional water. Infants can digest breast milk much more rapidly than formula and, therefore, do not get constipated. On average, it takes about 30 minutes longer to digest formula as opposed to breast milk. Breastfed babies have better cheekbone development and better jaw alignment.

Besides the benefits of the contracting uterus, the process of producing milk burns calories, which helps the mother to lose excess weight gained during pregnancy. After all, that is why pregnant women put on extra fat during pregnancyenergy storage for milk production. Breastfeeding is also related to a lower risk of breast cancer and ovarian cancer. For every year of life spent breastfeeding, a woman's risk of developing breast cancer drops by 4.3 percent and this is on top of the 7 percent reduction she enjoys for every baby to whom she gives birth.

Additionally, there is the convenience. Breast milk is always with the mother. Mothers do not have to store it. It is always at the right temperature. It is free. It does not require sterilization. In fact, it prevents diseases and has protective factors resulting in healthier babies and decreased healthcare costs. It saves money as there is no need to buy formula, bottles, and nipples.

Procedure

It is best to begin breastfeeding immediately after birth as it is an infant's natural instinct to nurse then. Regardless of the baby's initial suckling behavior, this interaction stimulates uterine contractions, promotes colonization of harmless bacteria on the nipple, and helps to protect the infant from pathogenic bacteria. It is an important time to nuzzle. Women breastfeed for a longer duration if feedings are started early. The first several feedings have an imprinting effect. It is recommended to continue feeding about every two to three hours. It is important to remember that all babies are different; some need to nurse almost constantly at first, while others can go much longer between feedings. There are babies and mothers who have no trouble breastfeeding, while others may need some assistance. Once the baby begins to suck, the mother makes sure that the entire dark area around the nipple (areola) is in the baby's mouth. This helps stimulate milk flow and allows the baby to get enough milk. Nipple soreness can be a result of the infant not getting a good grasp of the entire areola. A newborn needs to be fed at least eight to 12 times in 24 hours. Since breast milk is so easily digested, a baby may be hungry again as soon as one and one-half hours after the last feeding.

Mothers need to be comfortable when nursing; therefore, loose, front-opening clothes and a good nursing bra are essential. They need to explore different positions for breastfeeding to determine what is best for them. The cradle hold works well in bed or sitting in a comfortable chair. The football hold is excellent if the woman had a cesarean section . The mother can use pillows to support the baby and a footstool to flatten her

Lactation  
Signs of good breastfeeding  
progress Warning signs  
Eight to 12 feeding per 24 Fewer than eight feedings in 24 hours;
hours baby sleeps four to six hours at time
Baby nurses every 1.5 to Baby nurses every hour or more, but
three hours never seems satisfied
Six to eight wet diapers every Fewer than six wet diapers after the
24 hours after the third day third day
Soft yellow stools, about 1 Dark black, green, or brown stools
tablespoon or larger after the third day
After the third day, four to 10 Fewer than three or four stools per
stools per day day after the third day
Average daily weight gain of Baby does not regain birth weight by
15 to 30 g once milk comes in 10 days of age
Milk comes in; breasts are full Milk does not seem to come in by the
and warm and may leak milk fifth day
Intermittent periods of rhythmic Milk comes in, but sucking or
sucking and audible swallows swallowing is not audible
Breasts are tender and may be Sore and painful nipples throughout
slightly painful or sore most feedings; scabbed or cracked
nipples  
Breasts soften after a feed Severe engorgement; breast remain
  very hard after a feed

lap. The mother can position the baby's head by snuggling it in one arm and supporting her breast with the other hand by keeping her thumb well above the areola and the rest of the fingers below and under the breast (sometimes called the C-hold). In this position, the mother can lift her breast and guide her nipple in any direction as she helps the baby to take in more of the areola.

For early feedings, the infant should be offered both breasts at each feeding as this stimulates the need-supply response. The length of the feeding is up to the mother. The general rule is to watch the baby, not the clock. If, however, it is a first time mother, 20 to 30 minutes on the first side can be suggested. If the baby falls asleep at the breast, the next feeding should begin with the breast that was not nursed. Mothers can tell if the baby is getting enough milk by checking diapers; a baby who is wetting between four to six disposable diapers (six to eight cloth) and who has three or four bowel movements in 24 hours is getting enough milk.

Common problems

New mothers may experience nursing problems, including the following:

  • Engorgement: Breasts that are too full can prevent the baby from suckling because they cannot be grasped. Expressing milk manually or with a breast pump can alleviate this problem.
  • Sore nipples: Transient soreness can occur during the first week postpartum and is usually temporary. Air drying the nipples and rubbing colostrum or breast milk into them provides relief. Prolonged, abnormal soreness lasts longer than a week postpartum. Discontinuing use of soap on breasts while bathing and applying purified lanolin to nipples and air drying them helps.
  • Infection: Soreness and inflammation on the breast surface or a fever in the mother may be an indication of breast infection (mastitis). If it is just starting, the mother should drink lots of water and nurse frequently on the affected breast. Antibiotics may be necessary if the infection persists.

Lactation consultants work at almost every hospital where babies are delivered. First-time mothers can request the lactation consultant to visit her. The mother should make a note of the lactation consultant's phone number should problems be encountered after mother and infant go home.

There are no rules about when to stop breastfeeding. A baby needs breast milk for at least the first year of life and it is preferred that no solid food be given for at least the first six months to prevent allergies. As long as a baby eats age-appropriate solid food, the mother may nurse for several years.

Parental concerns

The majority of illnesses are not transmitted via breast milk; in fact, breast milk prevents many illnesses. However, some viruses, including HIV (the virus that causes AIDS can be passed in breast milk; for this reason, women who are HIV-positive should not breastfeed unless they are living in a country that does not have clean water to make formula. A lack of clean water to make formula could result in an infant dying from diarrhea.

Many medications have not been tested in nursing women, so it is not certain what drugs can affect a breastfed child. A nursing woman should always check with her doctor or lactation consultant before taking any medications, including over-the-counter drugs. The mother can usually take antibiotics without discontinuing breastfeeding.

The following drugs are not safe for a mother to take while she is nursing:

  • radioactive drugs for some diagnostic tests
  • chemotherapy drugs for cancer
  • bromocriptine
  • ergotamine
  • lithium
  • methotrexate
  • street drugs (including marijuana, heroin, amphetamines)
  • tobacco

KEY TERMS

Alveoli The tiny air sacs clustered at the ends of the bronchioles in the lungs in which oxygen-carbon dioxide exchange takes place.

Bromocriptine Also known as Parlodel, it is a dopamine receptor agonist used to treat galactorrhea by reducing levels of the hormone prolactin and is also used to treat Parkinson's disease.

Colostrum Milk secreted for a few days after birth and characterized by high protein and antibody content.

Ergotamine A drug used to prevent or treat migraine headaches. It can cause vomiting, diarrhea, and convulsions in infants and should not be taken by women who are nursing.

Involution The return of a large organ to normal size.

Lactogenesis The initiation of milk secretion.

Lithium A medication prescribed to treat the manic (excited) phases of bipolar disorder.

Mammary Relating to the breast.

Methotrexate A drug that interferes with cell growth and is used to treat rheumatoid arthritis as well as various types of cancer. Side-effects may include mouth sores, digestive upsets, skin rashes, and hair loss. Since this drug can supress an infant's immune system, it should not be taken by nursing mothers.

Placenta The organ that provides oxygen and nutrition from the mother to the unborn baby during pregnancy. The placenta is attached to the wall of the uterus and leads to the unborn baby via the umbilical cord.

Postpartum After childbirth.

Progesterone The hormone produced by the ovary after ovulation that prepares the uterine lining for a fertilized egg.

Prolactin A hormone that helps the breast prepare for milk production during pregnancy.

Resources

BOOKS

Behrmann, Barbara L. The Breastfeeding Café: Mothers Share the Joys, Challenges, and Secrets of Nursing. Ann Arbor, MI: University of Michigan Press, 2005.

Hanson, Lars A. Immunobiology of Human Milk: How Breastfeeding Protects Babies. Armillo, TX: Pharmasoft Publishing, 2004.

La Leche League International Staff. The Womanly Art of Breastfeeding. East Rutherford, NJ: Penguin Group, 2004.

Lim, Robin. Eating for Two: Recipes for Pregnant and Breastfeeding Women. Berkeley, CA: Celestial Arts Publishing, 2004.

Olds, Sally, et al. Maternal-Newborn Nursing & Women's Health Care, 7th ed. Saddle River, NJ: Prentice Hall, 2004.

Riordan, Jan. Breastfeeding and Human Lactation, 3rd ed. Boston, MA: Jones and Bartlett Publishers, 2004.

ORGANIZATIONS

International Lactation Consultants Association. 1500 Sunday Drive, Suite 102; Raleigh, NC 27607. Web site: <www.ilca.org/>.

La Leche League International. 1400 North Meacham Rd., Schaumburg, IL 60173. Web site: <www.lalecheleague.org/>.

National Alliance for Breastfeeding Advocacy. 9684 Oak Hill Drive; Ellicott City, MD 21042. Web site: <www.healthfinder.gov/orgs/HR2952.htm>.

Linda K. Bennington

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Bennington, Linda. "Lactation." Gale Encyclopedia of Children's Health: Infancy through Adolescence. 2006. Encyclopedia.com. 16 Apr. 2014 <http://www.encyclopedia.com>.

Bennington, Linda. "Lactation." Gale Encyclopedia of Children's Health: Infancy through Adolescence. 2006. Encyclopedia.com. (April 16, 2014). http://www.encyclopedia.com/doc/1G2-3447200332.html

Bennington, Linda. "Lactation." Gale Encyclopedia of Children's Health: Infancy through Adolescence. 2006. Retrieved April 16, 2014 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-3447200332.html

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Lactation

LACTATION

LACTATION. Lactation refers to the ability of mammals, warm-blooded, backboned animals, to nourish their young with milk produced by the mammary glands. Many other distinguishing features separate mammals into families that include over four thousand species. The milk of each species is specifically engineered for the growth and developmental needs of that species. In fact studies of the characteristics of the milk can predict the growth rate of both body and brain and the developmental maturity of the offspring at birth. It is also possible to predict the feeding patterns that vary from the whale, which feeds its young every three to four days and has extremely high-fat milk (50 percent), to the human, who initially feeds the infant every two to three hours and has low-protein, low-fat milk (3.4 percent). Some of the world's finest scientists have turned their attention to human lactation and have not only deciphered the micronutrients of human milk but have studied the nutrient needs of the human infant, especially as they pertain to brain development and physical growth. Research also has explained the physiology of human lactation.

Historically, in times of wealth and prosperity, women of higher socioeconomic levels have sought substitute feedings for their infants to "free" themselves of the burden of breast-feeding. Dogma and ritual have developed in different cultures of the world around nursing. It is significant that the Qur'an states that women should nurse their infants for two years. In the Old Testament, the Book of Psalms refers to the value of mother's milk. Pope John Paul II stated that the women of the world should provide their milk for their infants.

When bottle-feeding became more available for the average mother due to the discovery of sterilization, followed by the availability of prepared formulas, the trend toward bottle-feeding increased from 1930 to 1950. Well-educated women led the march to the bottle because they wanted to raise their infants by the book, with scientific information. In the second half of the twentieth century, these same educated women sought a different mode of childbirth in which the mother was prepared and in control. Concomitant with this, well-educated women began looking at breast-feeding as the most appropriate course for their infants.

In 1978 a bipartisan congressional committee charged with the responsibility of designing a health plan for the United States established the year 1990 as the target date for accomplishing several health goals. In addition to statements regarding decreasing hypertension, obesity, and smoking, the committee stated that 75 percent of women should leave the hospital breast-feeding and at least 35 percent should still be breast-feeding at six months. Many of the goals were not accomplished, and in 1990 they were rewritten with a target date of 2000. In 2000 they were rewritten for 2010, aiming at 75 percent of mothers initiating breast-feeding, 50 percent continuing for six months, and 25 percent continuing for a full year. The World Health Organization Code for Infant Feeding was developed in 1981, and the most industrialized countries of the world endorsed this policy, which supported breast-feeding and rejected the promotion of artificial feedings and advertisement of these feedings to the public. The United States did not sign until 1994. The Institute of Medicine, through the Subcommittee on Nutrition during Lactation, confirmed the position that all women, under ordinary circumstances, should breast-feed their infants and further stated that breast-feeding was ideal, even if the mother's diet was not perfect. The American Academy of Pediatrics, joined by the American College of Obstetrics and Gynecology, stated in 1997 that infants should be exclusively breast-fed for five to six months. They further stated that breast-feeding should continue as weaning foods are added through the first year of life and then for as long thereafter as the mother and the infant choose

Significance of Breast-Feeding to Health

Why have all of these important groups spoken out so strongly in favor of breast-feeding? The knowledge that human milk is for the human infant has been accepted for centuries. In the late twentieth century, however, considerable scientific investigation established unequivocally that breast-feeding is associated with a reduced incidence of infection in the infant, including reduced incidences of gastrointestinal, upper and lower respiratory, ear, and urinary tract infections. Immunologic data have shown reduced incidences of childhood-onset cancers, especially lymphoma and acute lymphocytic leukemia. Crohn's disease, celiac disease, and childhood-onset diabetes also are reduced when infants are breast-fed for at least four months. Probably the most dramatic information published in multiple articles is the relationship between breast-feeding and infant development. A study by Niles Newton compared the developmental progress of breast-fed and bottle-fed three-year-olds. Alan Lucas, Ruth Morley, T. J. Cole, and others reported a multisite study that compared premature babies given their mother's milk by feeding tube with infants given premature-infant formula. The group studied them at eighteen months and followed them until seven and a half to eight years of age. The study showed an 8.5-point difference when the data were adjusted for socioeconomic status and education of the mother. The eighteen-year study by L. John Horwood and David M. Fergusson in New Zealand showed a measurable difference at eighteen years of age in school outcomes and behaviors related to whether or not the children were breast-fed in infancy. Although these studies have been criticized for design flaws, many scientists accept their findings. These results are in addition to the compelling psychologic benefit to the mother and the infant in their relationship during breast-feeding.

Facilitating the Decision to Breast-Feed

A mother needs an opportunity to make an informed decision about how to feed her infant. If a mother comes to pregnancy without any information on this process, it is the health care provider's responsibility to see that she is well informed about the benefits of breast-feeding for her baby, for herself, and for society so she can make a decision that will be optimal.

The economic benefit of breast-feeding. A simple calculation of the cost of buying formula does not reflect completely the monetary benefits of breast-feeding. It costs between $60 and $80 a month to purchase infant formula, $700 to $1,000 for the first year of life. Careful studies in controlled populations, such as in health maintenance organizations, have demonstrated in multiple reports that infants who are not breast-fed have an increased number of illnesses, visits to the doctor, prescription medications, and hospitalizations compared with their breast-fed counterparts. The estimate per infant of the health care costs not to breast-feed is between $600 and $1,000 per year. This estimate does not include the reduction in the onset of chronic illnesses that may last a lifetime, such as diabetes, Crohn's disease, and allergies.

Benefits to the mother. The benefits of breast-feeding to the mother are often ignored. Women who breast-feed return to their prepregnant, physiologic states more rapidly. The uterus involutes, the postpartum blood loss is reduced, and the woman returns to her physiologic weight as well. Among other possible benefits are reduced incidences of long-term obesity, breast cancer, ovarian cancer, and most remarkably long-term osteoporosis. Although breast-feeding is not a contraceptive, it significantly affects the fertility in the childbearing years by suppressing ovulation.

Establishing lactation. Critical information about the mother's potential for a good milk supply is obtained during pregnancy. When the obstetrician does the early examination of the breasts in the first trimester, the breasts should be evaluated with respect to their potential for producing milk. Unusually small, unusually large, asym-metric, or tubular-shaped breasts may pose a problem. Prior surgery of the breast should be discussed. Lumpectomies and augmentation mammoplasty are not contraindications. Reduction mammoplasty, however, may pose a problem if the integrity of the ducts was interrupted. The obstetrician should also evaluate the breasts' responses to the hormones of pregnancy, the degree of increase in size of the breasts, and changes in the areola and nipple. The obstetrician should discuss with the mother her intentions to breast-feed and address any questions she may have. The mother should be encouraged to attend breast-feeding preparation classes, which are commonly available at hospitals with maternity services and at local mothers' groups.

The breast prepares for lactation during pregnancy by enhancing the ductal system and developing lacteal cells that will produce the milk. From about sixteen weeks in gestation on, the breast is capable of making milk if the fetus is delivered. During pregnancy the placenta produces a prolactin-inhibiting hormone (PIH) that blocks the breast from responding to the abundant prolactin of pregnancy. Once the placenta is delivered, the PIH drops, and the breast responds to the hormones oxytocin and prolactin.

The key response of the breast following delivery is called the ejection or letdown reflex, prompted by two major hormones, oxytocin and prolactin. Oxytocin causes myoepithelial cells to contract. Thus when the baby stimulates the breast by suckling, a message is sent via the peripheral nervous system to the mother's brain and pituitary to release oxytocin, which in turn causes the myoepithelial cells that surround the alveoli and the ductal system to contract, ejecting the milk from the ducts. Suckling at the breast also stimulates the release of prolactin, the hormone that stimulates the lacteal cells to produce milk. Prolactin is not released unless the breast is stimulated. Oxytocin, however, may be released when the mother sees her baby or hears her baby cry or as a result of other stimulating sensory pathways.

It is recommended that the infant be put to breast as soon after delivery as is possible. The infant has been sucking and swallowing in utero, consuming considerable amniotic fluid, from about fourteen weeks gestation on, so he or she is ready to begin breast-feeding.

To put the infant to breast, the infant is held with his or her abdomen against the mother's and the infant looking directly at the breast. The mother supports the breast with her hand, keeping her fingers behind the areola and gently compressing it. The mother strokes the center of the infant's lower lip with the nipple. This stimulates the infant to open his or her mouth, extend his or her tongue, and draw the nipple and the areola into his or her mouth. The baby's tongue compresses the elongated nipple and areola against his or her hard palate. The peristaltic motion of the tongue stimulates the letdown reflex, and milk is released and swallowed. Infants should be fed when hungry, which is eight to twelve times a day initially. No other food or drink is necessary during exclusive breast-feeding for up to six months.

See also Baby Food; Dairy Products; Milk, Human.

BIBLIOGRAPHY

American Academy of Pediatrics Work Group on Breastfeeding. "Breastfeeding and the Use of Human Milk." Pediatrics 100 (1997): 1035.

Ball, Thomas M., and Anne L. Wright. "Health Care Costs of Formula-Feeding in the First Year of Life." Pediatrics 103 (1999): 870.

Biancuzzo, Marie. Breastfeeding the Newborn: Clinical Strategies for Nurses. St. Louis, Mo.: Mosby, 1999.

Horwood, L. John, and David M. Fergusson. "Breastfeeding and Later Cognitive and Academic Outcomes." Pediatrics 101 (1998): 39.

Huggins, Kathleen. The Nursing Mother's Companion. 4th ed. Boston: Harvard Common Press, 1999.

Institute of Medicine, Subcommittee on Nutrition during Lactation. Nutrition during Lactation. Washington, D.C.: National Academy Press, 1991.

Lawrence, Ruth A., and Robert M. Lawrence. Breastfeeding: A Guide for the Medical Profession. 5th ed. St. Louis, Mo.: Mosby, 1999.

Lucas, Alan, Ruth Morley, T. J. Cole, et al. "Breast Milk and Subsequent Intelligence Quotient in Children Born Preterm." Lancet 339 (1992): 261.

Newton, Niles. "Psychological Differences between Breast and Bottle Feeding." American Journal of Clinical Nutrition 24 (1971): 993.

United States Department of Health and Human Services. Healthy People 2010. Conference ed. in 2 vols. Washington, D.C.: U.S. Department of Health and Human Services, 2000.

Ruth A. Lawrence

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Lactation

Lactation

Definition

Lactation is the medical term for yielding of milk by the mammary glands which leads to breastfeeding. Human milk contains the ideal amount of nutrients for the infant, and provides important protection from diseases through the mother's natural defenses.

Description

Early in a woman's pregnancy her milk-producing glands begin to prepare for her baby's arrival, and by the sixth month of pregnancy the breasts are ready to produce milk. Immediately after the baby is born, the placenta is delivered. This causes a hormone in the woman's body (prolactin) to activate the milk-producing glands. By the third to fifth day, the woman's breasts fill with milk.

Then, as the baby continues to suck each day, nursing triggers the continuing production of milk. The baby's sucking stimulates nerve endings in the nipple, which signal the mother's pituitary gland to release oxytocin, a hormone that causes the mammary glands to release milk to the nursing baby. This is called the "let-down reflex." While the baby's sucking is the primary stimulus for this reflex, a baby's cry, thoughts of the baby, or the sound of running water also may trigger the response. Frequent nursing will lead to increased milk production.

Breast milk cannot be duplicated by commercial baby food formulas, although both contain protein, fat, and carbohydrates. In particular, breast milk changes to meet the specific needs of a baby. The composition of breast milk changes as the baby grows to meet the baby's changing needs. Most important, breast milk contains substances called antibodies from the mother that can protect the child against illness and allergies. Antibodies are part of the body's natural defense system against infections and other agents that can cause disease. Breast milk also helps a baby's own immune system mature faster. As a result, breast-fed babies have less diarrhea and fewer ear infections, rashes, allergies, and other medical problems than bottle-fed babies.

There are many other benefits to breast milk. Because it is easily digested, babies do not get constipated. Breast-fed babies may have fewer speech impediments, and breastfeeding can improve cheekbone development and jaw alignment.

Breastfeeding is also good for the mother. The act of breastfeeding releases hormones that stimulate the uterus to contract, helping it to return to normal size after delivery and reducing the risk of bleeding. The act of producing milk is thought to burn more calories, helping the mother to lose excess weight gained during pregnancy. However, research in 2004 disputed this belief when body composition changes of lactation and non-lactating women were compared at intervals for six months postpartum. Breastfeeding may be related to a lower risk of breast cancer, ovarian cancer, or cervical cancer. This benefit is stronger the younger a woman is when she breastfeeds; women who breastfeed before age 20 and nurse for at least six months have a 50% drop in the risk for breast cancer.

In addition, breastfeeding does not involve any formulas, bottles and nipples, or sterilizing equipment. Breast milk is free, and saves money by eliminating the need to buy formula, bottles, and nipples. Because breast-fed babies are healthier, health care costs for breast-fed infants are lower.

Procedure

Breastfeeding should begin as soon as possible after birth, and should continue every two to three hours. However, all babies are different; some need to nurse almost constantly at first, while others can go much longer between feedings. A baby should be fed at least 8-12 times in 24 hours. Because breast milk is easily digested, a baby may be hungry again as soon as one and one-half hours after the last meal.

Mothers should wear comfortable, loose, front-opening clothes and a good nursing bra. Mothers should find a comfortable chair with lots of pillows, supporting the arm and back. Feet should rest on a low footstool, with knees raised slightly. The baby should be level with the breast. The new mother may have to experiment with different ways of holding the baby before finding one that is comfortable for both the mother and baby.

Some babies have no trouble breastfeeding, while others may need some assistance. Once the baby begins to suck, the mother should make sure that the entire dark area around the nipple is in the baby's mouth. This will help stimulate milk flow, allowing the baby to get enough milk. It will also prevent nipple soreness.

Breastfeeding mothers will usually offer the baby both breasts at each feeding. Breastfeeding takes about 15-20 minutes on each side. After stopping the feeding on one side, the mother should burp the baby before beginning the feeding on the other breast. If the baby falls asleep at the breast, the next feeding should begin with the breast that was not nursed.

Mothers can tell if the baby is getting enough milk by checking diapers; a baby who is wetting between four to six disposable diapers (six to eight cloth) and who has three or four bowel movements in 24 hours is getting enough milk.

Nursing problems

New mothers may experience nursing problems, including:

  • Engorged breasts. Breasts that are too full can prevent the baby from sucking. Expressing milk manually or with a breast pump can help.
  • Sore nipples. In the early weeks nipples may become sore; a nipple shield can ease discomfort.
  • Infection. Soreness and inflammation on the breast surface or a fever in the mother, may be an indication of breast infection. Antibiotics and continued nursing on the affected side may solve the problem.

Prognosis

There are no rules about when to stop breastfeeding. A baby needs breast milk for at least the first year of life; as long as a baby eats age-appropriate solid food, the mother may nurse for several years.

Prevention

Most common illnesses can not be transmitted via breast milk. However, some viruses, including HIV (the virus that causes AIDS ) can be passed in breast milk; for this reason, women who are HIV-positive should not breastfeed.

Many medications have not been tested in nursing women, so it is not known if these drugs can affect a breast-fed child. A nursing woman should always check with her doctor before taking any medications, including over-the-counter drugs.

These drugs are not safe to take while nursing:

  • Radioactive drugs for some diagnostic tests
  • Chemotherapy drugs for cancer
  • Bromocriptine
  • Ergotamine
  • Lithium
  • Methotrexate
  • Street drugs (including marijuana, heroin, amphetamines)
  • Tobacco.

KEY TERMS

Bromocriptine A drug used to treat Parkinson's disease that can decrease a woman's milk supply.

Ergotamine A drug used to prevent or treat migraine headaches. This can cause vomiting, diarrhea, and convulsions in infants.

Lithium A drug used to treat manic depression (bipolar disorder) that can be transmitted in breast milk.

Methotrexate An anticancer drug also used to treat arthritis that can suppress an infant's immune system when taken by a nursing mother.

Resources

PERIODICALS

Wosje, Karen S., and Heidi J. Kalkwarf. "Lactation, Weaning, and Calcium Supplementation: Effects on Body Composition in Postpartum Women." American Journal of Clinical Nutrition August 2004: 676.

ORGANIZATIONS

International Lactation Consultants Assoc. 201 Brown Ave., Evanston, IL 60202. (708) 260-8874.

La Leche League International. 1400 North Meacham Rd., Schaumburg, IL 60173. (800) LA-LECHE.

National Alliance for Breastfeeding Advocacy. 254 Conant Rd., Weston, MA 02193. (617) 893-3553.

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lactation

lactation The process of synthesizing and secreting milk from the breasts.

Lactating women have slightly increased energy and protein requirements compared with those who are not breast‐feeding (although considerable reserves of fat are laid down in pregnancy to cope with the stress of lactation), and high requirements for iron and calcium. These increased needs are reflected in the increased reference intakes for lactating women.

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DAVID A. BENDER. "lactation." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. 16 Apr. 2014 <http://www.encyclopedia.com>.

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DAVID A. BENDER. "lactation." A Dictionary of Food and Nutrition. 2005. Retrieved April 16, 2014 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O39-lactation.html

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lactation

lactation (lak-tay-shŏn) n. the secretion of milk by the mammary glands of the breasts, which begins normally at the end of pregnancy (see also colostrum) and is stimulated by the sucking of the baby at the nipple (compare galactorrhoea). Lactation is controlled by hormones (see prolactin, oxytocin); it stops when the baby is no longer breast-fed.

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"lactation." A Dictionary of Nursing. 2008. Encyclopedia.com. 16 Apr. 2014 <http://www.encyclopedia.com>.

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lactation

lactation Secretion of milk to feed the young. In pregnant women, hormones induce the breasts to enlarge, and prolactin (a hormone of the pituitary gland) stimulates breast cells to begin secreting milk. The milk appears in the breast immediately after the birth of the baby. The hormone oxytocin controls the propulsion of milk from the breast.

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"lactation." World Encyclopedia. 2005. Encyclopedia.com. 16 Apr. 2014 <http://www.encyclopedia.com>.

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"lactation." World Encyclopedia. 2005. Retrieved April 16, 2014 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-lactation.html

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lactation

lactation The discharge of milk from the mammary glands. This generally only occurs after birth of the young and is stimulated by the sucking action of the infants. Lactation is under the control of hormones, notably prolactin and oxytocin.

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"lactation." A Dictionary of Biology. 2004. Encyclopedia.com. 16 Apr. 2014 <http://www.encyclopedia.com>.

"lactation." A Dictionary of Biology. 2004. Encyclopedia.com. (April 16, 2014). http://www.encyclopedia.com/doc/1O6-lactation.html

"lactation." A Dictionary of Biology. 2004. Retrieved April 16, 2014 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-lactation.html

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