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    How Milk is Produced

    The breast is a gland which consists primarily of connective and fatty tissues that support and protect the milk producing areas of the breast. The milk is produced in small clusters of cells called alveoli and travels down the milk ducts to the milk sinuses, which act as a collecting reservoir. The sinuses are located behind the areola, the pigmented area around your nipple. (See illustration below.)

    Breastfeeding success has nothing to do with the size of the breasts or nipples. Breast size is an inherited trait and determined by the number of fat cells you have. The breasts will enlarge with pregnancy and lactation. Breastfeeding is a supply and demand process — the more you nurse, the more milk you produce.

    Anatomy of the Female Breast

    Side view of Breast showing Montgomery Glands, Nipple, and AreolaThe nipple and areola (the dark area around the nipple) enlarge and darken during pregnancy. This may assist your baby in latching-on by providing a more distinct “target.”

    The small bumps on the areola are called Montgomery Glands. They produce a natural oil which cleans, lubricates, and protects the nipple during pregnancy and breastfeeding. The oil contains a bacteria-killing enzyme and makes breast creams unnecessary.

    Cross-sectional view of Breast showing Duct, Sinus, Nipple Opening, Areola, and Milk-producing CellsUse only water to clean your breasts. Soaps, lotions, or alcohol might remove this protective oil.

    Each nipple has 15 to 20 openings for milk to flow. When your baby nurses, the action of baby's jaws and tongue pressing down on the milk sinuses creates a suction that causes the milk to flow out of your breast and into your baby's mouth.

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    The Let-Down Reflex

    Infant suckling stimulates the nerve endings in the nipple and areola, which signal the pituitary gland in the brain to release two hormones, Prolactin and Oxytocin.

    How Your Breast Responds to Your Baby's Suckling

    • Prolactin causes your alveoli to take nutrients (proteins, sugars) from your blood supply and turn them into breast milk.

    • Oxytocin causes the cells around the milk ducts to contract and eject milk from the milk glands and down the milk ducts. This passing of the milk down the ducts is called the “let-down” (milk ejection) reflex.

    • Let-down is experienced in numerous ways including:

      • your infant begins to actively suck and swallow;

      • milk may drip from the opposite breast;

      • the mother may feel a tingling or a full sensation (after the first week of nursing) in your breasts, or uterine cramping.
    NOTE: There may be many let-downs during a feeding, of which you may or may not be aware. Because the brain is directly involved in the release of hormones which enable the milk to be produced and ejected, let-downs may occur in other situations, such as when you think about your baby or hear your or another baby cry, when it is your scheduled nursing time, or when you are sexually stimulated or during orgasm.

    If the let-down occurs at an awkward time, cross your arms over your chest, or press the heel of your hand over the nipple area and apply pressure until the leaking stops. It may also help to wear cotton breast pads (without plastic liners) in your bra, especially in the first weeks, to protect your clothing. This type of response will usually diminish after the first few weeks of nursing.

    Uterus Response Postpartum
    Release of the hormone oxytocin while breastfeeding will also cause the uterus to contract; this may be more noticeable if you have previously had children.

    Interference with Let-down
    A variety of factors may interfere with let-down:
    • Emotions: embarrassment, anger, irritation, fear, or resentment

    • Fatigue

    • Inadequate sucking (Improper positioning or insufficient amount of time baby is actively nursing)

    • Lack of privacy

    • Stress

    • Negative remarks from relatives or friends

    • Fear of pain in your breasts or uterus (i.e., sore nipples or after birth pains)

    • Breast engorgement in the first few days
    Suggestions for Creating a Supportive Nursing Environment
    • Find a peaceful atmosphere for nursing. Before beginning the feeding, unplug the phone, turn on relaxing music, and do deep breathing. (Take four or five deep abdominal breaths.)

    • If breastfeeding in public inhibits you, insist on your privacy and/or drape a light cover over your baby and your shoulder.

    • Interact with friends and breastfeeding professionals who are supportive of breastfeeding. Don't let well-meaning friends and relatives who have different attitudes discourage you. Restrict visitors until you are comfortable.

    • Be around other nursing mothers. Attend a postpartum exercise class and/or support group.

    • Be sure your baby is positioned properly and allow adequate sucking time.

    • Prepare your breasts for nursing:

      • Take a warm bath or place warm towels over your breasts before nursing;

      • Massage the breast tissue to help increase the milk flow.

      • If you are having difficulty and your baby is becoming frustrated, change breasts several times during a feeding.

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    Your Milk: Colustrum and Mature Milk

    Colostrum is the early milk made by your breasts, and is usually present after the fifth or sixth month of pregnancy. Once the baby is born, it is present in small amounts for the first 3 days to match the small size of the baby's stomach. Most babies do not need additional nutrition during this time. Begin breastfeeding as soon as possible after giving birth and every 1 to 3 hours per 24 hours (8-12 times per 24 hours) to allow your baby to receive this valuable milk.

    Colostrum is designed to meet the special needs of a newborn. Colostrum has a yellow color, feels thick, and is high in protein and low in fat and sugar. The protein content is three times higher than mature milk because it is rich in the immunities being passed from the mother to protect the baby. It also acts as a natural laxative, helping the baby pass the first stools called meconium.

    Mature Milk
    Your milk will change and increase in quantity in approximately 48 to 72 hours. It may take longer depending on when breastfeeding was initiated and breastfeeding frequency. The change in milk occurs a little earlier if you have breastfed before.

    • Foremilk: When breastfeeding is initiated, the first milk the baby receives is called foremilk, which appears thin and watery with a light blue tinge. Foremilk is composed largely of water and is necessary to satisfy your baby's thirst.

    • Hind-milk: Hind-milk has the highest concentration of fat and is released after several minutes of nursing. It is similar in consistency to cream and will have a soporific (sleepy) effect on your baby. Hind-milk is important for your baby to feel satisfied and to gain adequate weight. Feed your baby until you see a sleepy, satisfied look on his/her face.
    NOTE: "Weak breast milk" does not exist. Your body will combine the exact ingredients necessary to meet your baby's requirements.

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    The Family's Role

    Breastfeeding is usually thought to include only a mother and baby. However, the family also plays a major role in the breastfeeding relationship. One of the most precious gifts family members can give the mother is to take care of her and encourage and support a healthy breastfeeding relationship.

    Family can do the many household tasks that take a mother's energy away from nursing her baby. Help her find and use the lactation resources in her community if she is having any problems breastfeeding.

    There are many other satisfying ways for the family to participate in caring for the baby, besides feeding him/her. Activities such as burping, diapering, playing, giving the baby massages, comforting (holding and rocking, etc.) and taking the baby for a walk are wonderful ways to help, as well as get to know the baby. Bathing is a very special activity because bath time is a great opportunity for eye contact and play for the whole family.

    Helping and encouraging the breast feeding mother are the most important things in assisting her to establish successful breastfeeding. The first few weeks of breastfeeding are critical for the new mother and her baby to learn what works best for the two of them. This is also when her milk supply is being established. This time can be very frustrating after just having gone through labor and delivery. The mother may be physically and emotionally drained. You and your baby may need to try several breastfeeding positions before you find the one(s) that works. With strong support from family, friends, health professionals and volunteer counselors, mothers who would otherwise have given up breastfeeding during the first weeks are able to succeed.

    A Good Support Network
    A good support network can assist in many ways. They can help get you complete, accurate information about breastfeeding and resolve any problem(s) quickly. By doing other “duties”, your support network can allow you to put all your efforts into breastfeeding and getting to know your baby. Most importantly, they can help you feel confident in your ability to breastfeed your baby.

    The most important support person for most new mothers is their husband or partner. Other support persons may include the new mother's mother, other immediate and extended family members, friends who have breastfed, health professionals such as the obstetrician, pediatrician, lactation consultant, and volunteer counselors such as those at Nursing Mothers Counsel, La Leche or other local breastfeeding support groups in the community.

    How can family and friends provide support?
    The best thing they can do is to attend a breastfeeding class with you. In this class, they will learn about the benefits of breastfeeding, how to establish a good milk supply, and how to manage common breastfeeding problems. Your own mother may or may not have breastfed you, as many mothers in her generation did not. Either way, she can learn new things from a breastfeeding class, as there is a lot of new information on breastfeeding and its benefits. Sometimes even well intentioned family and friends can put your milk supply at risk by giving your baby bottles, pacifiers, advising you to limit nursing time or encouraging you to "get the baby on a schedule." The more your partner and family know about breastfeeding, the more they can help you.

    It is also extremely important that your support people provide encouragement and emotional support during the first days when you and the baby are learning how to breastfeed. Many mothers decide to give up on breastfeeding during this period. Remember that it will take time for both you and your baby to get comfortable with breastfeeding. Even if you have breastfed before, each baby is different. You and your baby will learn what works best for the two of you during the first several days or weeks together.

    Your support people can help you with other household tasks such as cleaning, laundry, shopping and meal preparation. Physical fatigue from trying to do too much can affect your milk supply. Nap when your baby sleeps to assist in your physical recovery. Exhaustion can make postpartum depression (some women feel "low" or "depressed" after delivery) worse. Let others do things for you. Only you can breastfeed your baby so you should put all of your efforts into recovering from your delivery, breastfeeding and getting to know your baby.

    Resuming Intimacy
    Finally, you and your partner should both be patient about resuming intimacy. You may temporarily lose interest in having sex after giving birth. This is common and can happen regardless of whether or not you are breastfeeding. You may have concerns and negative feelings about your body after pregnancy and delivery. Breastfeeding does not "ruin your breasts." Although you may experience breast changes after childbirth, these changes were caused by pregnancy, not by breastfeeding. Breastfeeding does not make you gain weight; in fact, along with proper diet and moderate exercise, it may help you lose your pregnancy weight more easily.

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