Breastfeeding

Breastfeeding is the feeding of an infant or young child with breast milk directly from female human breasts (i.e., via lactation) rather than from a baby bottle or other container. Babies have a sucking reflex that enables them to suck and swallow milk. It is recommended that mothers breastfeed for six months or more, without the addition of infant formula or solid food. After the addition of solid food, mothers are advised to continue breast-feeding up to a year, and can continue for two years or more.

Human breast milk is the healthiest form of milk for babies. There are few exceptions, such as when the mother is taking certain drugs or is infected with human T-lymphotropic virus, HIV, or has active untreated tuberculosis. Breastfeeding promotes health and helps to prevent disease. Artificial feeding is associated with more deaths from diarrhea in infants in both developing and developed countries. Experts agree that breastfeeding is beneficial, and have concerns about artificial formulas but there are conflicting views about how long exclusive breastfeeding remains beneficial.

The World Health Organization (WHO) and the American Academy of Pediatrics (AAP) emphasize the value of breastfeeding for mothers as well as children. Both recommend exclusive breastfeeding for the first six months of life and then supplemented breastfeeding for at least one year and up to two years or more. While recognizing the superiority of breastfeeding, regulating authorities also work to minimize the risks of artificial feeding.

Breast milk

Not all the properties of breast milk are understood, but its nutrient content is relatively stable. Breast milk is made from nutrients in the mother's bloodstream and bodily stores. Breast milk has just the right amount of fat, sugar, water, and protein that is needed for a baby's growth and development. Because breastfeeding uses an average of 500 calories a day it helps the mother lose weight after giving birth.The composition of breast milk changes depending on how long the baby nurses at each session, as well as on the age of the child. The quality of a mother's breast milk may be compromised by smoking, alcoholic beverages, caffeinated drinks, marijuana, methamphetamine, heroin, and methadone.

Benefits for the infant

Scientific research, such as the studies summarized in a 2007 review for the U.S. Agency for Healthcare Research and Quality (AHRQ) and a 2007 review for the WHO, has found many benefits to breastfeeding for the infant. These include:

Greater immune health

During breastfeeding, antibodies pass to the baby. This is one of the most important features of colostrum, the breast milk created for newborns. Breast milk contains several anti-infective factors such as bile salt stimulated lipase (protecting against amoebic infections), lactoferrin (which binds to iron and inhibits the growth of intestinal bacteria) and immunoglobulin A protecting against microorganisms.

Fewer infections

Among the studies showing that breastfed infants have a lower risk of infection than non-breastfed infants are:

In a 1993 University of Texas Medical Branch study, a longer period of breastfeeding was associated with a shorter duration of some middle ear infections (otitis media with effusion) in the first two years of life.

A 1995 study of 87 infants found that breastfed babies had half the incidence of diarrheal illness, 19% fewer cases of any otitis media infection, and 80% fewer prolonged cases of otitis media than formula fed babies in the first twelve months of life.

Breastfeeding appeared to reduce symptoms of upper respiratory tract infections in premature infants up to seven months after release from hospital in a 2002 study of 39 infants.

A 2004 case-control study found that breastfeeding reduced the risk of acquiring urinary tract infections in infants up to seven months of age, with the protection strongest immediately after birth.

The 2007 review for AHRQ found that breastfeeding reduced the risk of acute otitis media, non-specific gastroenteritis, and severe lower respiratory tract infections.

Benefits for mothers

Breastfeeding is a cost effective way of feeding an infant, providing nourishment for a child at a small cost to the mother. Frequent and exclusive breastfeeding can delay the return of fertility through lactational amenorrhea, though breastfeeding is an imperfect means of birth control. During breastfeeding beneficial hormones are released into the mother's body and the maternal bond can be strengthened.Breastfeeding is possible throughout pregnancy, but generally milk production will be reduced at some point.

Bonding

Hormones released during breastfeeding help to strengthen the maternal bond. Teaching partners how to manage common difficulties is associated with higher breastfeeding rates. Support for a mother while breastfeeding can assist in familial bonds and help build a paternal bond between father and child.

If the mother is away, an alternative caregiver may be able to feed the baby with expressed breast milk. The various breast pumps available for sale and rent help working mothers to feed their babies breast milk for as long as they want. To be successful, the mother must produce and store enough milk to feed the child for the time she is away, and the feeding caregiver must be comfortable in handling breast milk.

Hormone release

Breastfeeding releases oxytocin and prolactin, hormones that relax the mother and make her feel more nurturing toward her baby. Breastfeeding soon after giving birth increases the mother's oxytocin levels, making her uterus contract more quickly and reducing bleeding. Pitocin, a synthetic hormone used to make the uterus contract during and after labour, is structurally modelled on oxytocin. Syntocinon, another synthetic oxytocic, is commonly used in Australia and the UK rather than Pitocin.

Weight loss

As the fat accumulated during pregnancy is used to produce milk, extended breastfeeding—at least 6 months—can help mothers lose weight. However, weight loss is highly variable among lactating women; monitoring the diet and increasing the amount/intensity of exercise are more reliable ways of losing weight. The 2007 review for the AHRQ found "The effect of breastfeeding in mothers on return-to-pre-pregnancy weight was negligible, and the effect of breastfeeding on postpartum weight loss was unclear."

Natural postpartum infertility

Breastfeeding may delay the return to fertility for some women by suppressing ovulation. A breastfeeding woman may not ovulate, or have regular periods, during the entire lactation period. The period in which ovulation is absent differs for each woman. This lactational amenorrhea has been used as an imperfect form of natural contraception, with greater than 98% effectiveness during the first six months after birth if specific nursing behaviors are followed. It is possible for women to ovulate within two months after birth while fully breastfeeding and get pregnant again.

Long-term health effects

For breastfeeding women, long-term health benefits include:

Less risk of breast cancer, ovarian cancer, and endometrial cancer.

A 2009 study indicated that lactation for at least 24 months is associated with a 23% lower risk of coronary heart disease.

Although the 2007 review for the AHRQ found "no relationship between a history of lactation and the risk of osteoporosis", mothers who breastfeed longer than eight months benefit from bone re-mineralisation.

Breastfeeding diabetic mothers require less insulin.

Reduced risk of metabolic syndrome

Reduced risk of post-partum bleeding.

According to a Malmö University study published in 2009, women who breast fed for a longer duration have a lower risk for contracting rheumatoid arthritis than women who breast fed for a shorter duration or who had never breast fed.