IMPORTANT NOTICE: Breastfeeding is the best source of infant nutrition. Good maternal nutrition is important for preparation and maintenance of breastfeeding. When infant formula are to be used, a mother should be aware of the negative effect on breastfeeding along with financial and social implications of formula feeding, the difficulty of reversing the decision not to breastfeed, and the care that must be taken to prevent partial formula feeding from interfering with lactation. A health-care professional should be consulted before initiating formula feeding.