Lactation Health Article

Definition

Lactation is the medical term used for breastfeeding. It also specifically refers to the synthesis and secretion of milk.

Purpose

Breastfeeding provides a baby with nutrition in the form of breast milk. Not only does breast milk contain all the nutrients needed by a rapidly developing newborn, but it also contains antibodies that provide the baby with additional protection from common early childhood diseases.

Precautions

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

Description

Early in a woman's pregnancy her milk-producing glands, called mammary glands, begin to prepare for the baby's arrival and by the sixteenth week of pregnancy the breasts are ready to produce milk. Shortly after the baby is born, the expulsion of the placenta triggers hormone shifts in the woman's body to activate lactation. The levels of the hormones estrogen and progesterone fall abruptly while the level of the hormone prolactin—the main hormone involved in the biosynthesis of milk— increases. The anterior pituitary gland secretes prolactin during lactation in very large quantities so that by 36 to 96 hours postpartum the woman's milk volume has dramatically increased. Subsequently, the volume of milk the mother produces levels off and the removal of milk becomes the predominant factor in regulating milk production.

Another hormone called oxytocin controls the release of milk from the breasts. The baby's sucking stimulates nerve endings in the nipple, which signal the mother's pituitary gland to release the oxytocin. This is called the "let-down reflex." While the baby's sucking is the primary stimulus for the reflex, a baby's cry, thoughts of the baby, or the sound of running water also may trigger the response.

Breast milk cannot be duplicated by artificial milk, although both contain protein, fat, and carbohydrates. Breast milk changes to meet the specific needs of a baby.

In particular, the mother produces milk called colostrum at the end of pregnancy and in the initial postpartum period. Colostrum is called "first milk" and is thicker than mature milk. It is yellowish in color and is rich in proteins, many of which are immunoglobulins that can protect the child against illness and allergies. Immunoglobuoins 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 fewer ear infections, bouts of diarrhea, rashes, allergies, and other medical problems than bottle-fed babies do.

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

Breastfeeding is also good for the mother. It releases hormones that stimulate the uterus to contract, helping the uterus to return to normal size after delivery and reducing the risk of bleeding. The act of producing milk burns calories, which helps the mother to lose excess weight gained during pregnancy. Breastfeeding also may be related to a lower risk of breast cancer, ovarian cancer, and cervical cancer.

Breast milk is free, and saves money by eliminating the need to buy artificial milk (formula), bottles, and nipples. Because breast-fed babies overall have fewer illnesses, their health care costs may be lower.

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 very frequently at first, while others can go much longer between feedings. A baby should be fed at least eight to 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. Frequent nursing will also help in increasing milk production.

Some babies have no trouble breastfeeding, while others may need some assistance. Once the baby begins to suck, the mother should make sure that most of the areola is in the baby's mouth. Proper latching-on will help stimulate milk flow and will prevent nipple soreness.

Breastfeeding mothers should 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. The next feeding should begin with the breast that the baby nursed on last.

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.