Artificial infant feeding (AIF) is one of the most successful and widely used reproductive technologies to date. It can completely replace the lactation function of women's breasts that was once essential for the continuation of human life. Breastfeeding rates in industrialized countries most likely began a slow decline in the eighteenth century, but significant changes occurred in the first half of the twentieth century, coinciding with improvements in AIF. After World War II, breastfeeding rates declined dramatically. Estimates of breastfeeding rates by 1970 in the United States range from 18 percent to 25 percent at birth, decreasing to about 5 percent at six months of age. A renewed interest both within the scientific community and among many women who desired to experience the full range of their reproductive abilities led to an increase, peaking in the early 1980s, when 59.7 percent of new mothers breastfed at birth. A slow but persistent decline then occurred, reaching a low in 1990, when 51.5 percent of new- borns were breastfeeding. Since then, breastfeeding has slowly increased. However, breastfeeding with supplemental foods rather than exclusive breastfeeding accounts for much of this increase. Also, the duration appears to be declining, and surveys suggest that much of the discontinuation actually occurs early in the postpartum period.
There are large discrepancies in breastfeeding rates of women from different social categories. In industrialized countries, women from the less privileged minority groups and economic levels have significantly lower