This report estimates of different fertility measures for both men and women in the United States for the period 2006–2010. Fertility refers to the number of live births that occur to an individual. In 2008, there were 4.2 million births in the United States. The average fertility of women in the United States was about seven children at the beginning of the 19th century, it declined slowly and by 1960 it was 3.7 children per woman (2,3). Fertility in the United States dropped to its lowest point in 1976 at an average of 1.7 children per woman and has remained relatively stable at around 2.1 children per woman.
While fertility in the United States has remained stable since the 1970s, there is variation by subgroups including age, race, ethnicity, education, and measures of socioeconomic status. Researchers have often examined the intermediate characteristics that help to explain fertility such as fecundity (the ability to have children), timing of sexual intercourse, time spent in sexual relationships, and use of contraception. Others have looked at timing of fertility, the composition of those who have children, the number of children born, the union status at childbirth, etc.
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