Two 25-milliliter samples of human breast milk. The lefthand snow condensed milk 60ml is first milk produced and the righthand sample is milk produced later during the same pumping. The World Health Organization recommends exclusive breastfeeding for the first six months of life, with solids gradually being introduced around this age when signs of readiness are shown.
Supplemented breastfeeding is recommended until at least age two and then for as long as the mother and child wish. Breastfeeding offers health benefits to mother and child even after infancy. Breastfeeding also provides health benefits for the mother. It assists the uterus in returning to its pre-pregnancy size and reduces post-partum bleeding, as well as assisting the mother in returning to her pre-pregnancy weight. Breastfeeding also reduces the risk of breast cancer later in life.
Though it now is almost universally prescribed, in some countries in the 1950s the practice of breastfeeding went through a period where it was out of vogue and the use of infant formula was considered superior to breast milk. However, it is now universally recognized that there is no commercial formula that can equal breast milk. At around four months of age, the internal iron supplies of the infant, held in the hepatic cells of the liver, are exhausted, hence this is the time that an iron supplement should be introduced. Under the influence of the hormones prolactin and oxytocin, women produce milk after childbirth to feed the baby.
Actual inability to produce enough milk is rare, with studies showing that mothers from developing countries experiencing nutritional hardship still produce amounts of milk of similar quality to that of mothers in developed countries. There are many reasons a mother may not produce enough breast milk. Sodium concentration is higher in hand-expressed milk, when compared with the use of manual and electric pumps, and fat content is higher when the breast has been massaged, in conjunction with listening to relaxing audio. This may be important for low birthweight infants. Breast milk contains complex proteins, lipids, carbohydrates and other biologically active components. The composition changes over a single feed as well as over the period of lactation.