1.2 Growth through Natural Increase: Births

While the influx of immigrants contributed to the growth of the American population and helped build American society, the major factor affecting population growth in the United States has always been the surplus of births over deaths, or the natural increase of the population. American women at the beginning of the 21st century bear an average of two children over the course of their lives. Their great-grandmothers and great-great-grandmothers in 1890 had an average of four children, because in the 19th century fewer women had access to reliable methods for controlling fertility. A century earlier, around 1790, women might expect seven births throughout their lives, if they survived into their late 40s.

1.2.1 Birthrates in Early America

Little is known of the birthrates of Native American societies before the arrival of Europeans. There are hints that the birthrate was relatively low because Native American women often breastfed their infants for three or four years. Since breastfeeding has a contraceptive effect, it appears that women gave birth about every four years. On the other hand, since many Native American women traditionally married soon after the onset of puberty, at around age 15, they might have had six or seven children if they lived to at least age 45. Some researchers have suggested that when European diseases and warfare killed large numbers of native peoples, women increased their childbearing in order to compensate for the excessive deaths in the community. Native Americans may have gone from low birthrates to high birthrates, but any increases in fertility could not make up for the deaths from disease, starvation, and war. The birthrate among Native Americans would not produce population growth until the 20th century.

European colonists had high birthrates compared with the birthrates in Europe at the time. Free, white colonial women typically bore children every two years and had an average of eight children, four of whom might survive to adulthood. This was twice as many children as European families had. Fertility was higher in the colonies because of the need for labor on colonial farms, the availability of land to support the larger numbers of children, and early and nearly universal marriage.

The enslaved African American population in the 17th century had more men than women and more deaths than births. By the 18th century the ratio of black men to black women was more equal and the population was holding its own. By the early 19th century the African American population was growing rapidly, but because of higher death rates and the absence of immigration after 1808, the overall growth of the African American population remained lower than that of the white population. African Americans became an increasingly smaller proportion of the population from the late 18th century to the early 20th century.

1.2.2 Declining Birthrates

The European American population doubled every 20 to 25 years until late in the 18th century, after which birthrates began to decrease and growth rates slowed. This decline in fertility rates early in America’s history is a distinctive characteristic of American society. In the early 19th century white women who lived through their childbearing years were bearing 7 children over the course of their lives; by 1850 it was 5.4 children, by 1950 it was 3.0, and in 2002 it was 2.1. While the longer-established American population experienced a decline in fertility and family size during the 19th century, newer immigrants had higher birthrates. It took two or three generations for these immigrants to conform to the prevailing American fertility standards.

Здесь есть еще два под-под-под-раздела, я их опустил.