American fertility has gone through dramatic changes in the past century, including the "baby boom" after World War II and the "baby bust" of the 1960s and 1970s, which brought births below the replacement level of 2.11 births per woman for the first time in recorded history. In contrast, the average American woman in 1800 gave birth to seven children.
Back then, the U.S. was an agrarian society, so children had economic value. Cities saw a trend toward lower fertility: Families in Nantucket, for example, began limiting the number of children as early as the 1730s. Raising kids was costly, and, being whalers, residents had less incentive to have many children. Birth rates began dropping nationally during the 19th century because of urbanization and the decreasing supply of farmland, which lessened the need for extra hands. The most popular methods of family limitation were coitus interruptus, followed by the douche and the condom. By 1930 the U.S. birth rate had fallen to about a third of that recorded in 1800.
This article was originally published with the title Fertility Volatility.