OF ALL THE LIFE CHOICES men and women make, none is more important for society, none has more far-reaching consequences, none represents a more complete blending of economic, social, biological, and emotional forces than the decision to bring an-other life into the world. For an individual, the timing and circumstances of birth significantly affect the character, quality, and duration of life. For a society, the birth rate is a major determinant of its economic, political, and social development. Let the rate exceed society’s capacity to provide the necessities of life, and the outcome will be the poverty and misery so graphically described by Thomas Malthus. Let the rate fall below the replacement ratio, and the society is on its way to extinction.
U.S. fertility is now only one-fourth of what it was in 1800 and has been below replacement level since 1973. We will examine the long-term downward trend in the light of changes in the costs and benefits of children and changes in the cost of preventing births. The economic perspective will also help us understand why the number of births per thousand women of childbearing age rose by 67 percent from 1936 to 1957 and then fell by 55 percent during the following two decades.