The purpose of this report is to draw together statistics from various sources to provide the user with a convenient and comprehensive portrayal of trends and differentials in fertility in the United States. These sources include the Bureau of the Census, the National Center for Health Statistics, and privately conducted surveys.

The focus in this report is on trends and differentials in fertility during the last decade; however, in some tables, time series extending back 50 years are shown to provide perspective.

Because the measures of fertility used in the report and the interpretation of these measures may not be familiar to the reader, the tables in each section are preceded by a brief discussion of methodology.

Following is a summary of the major trends and differentials in fertility in the United States:

1. Recent trends infertility. In 1969 and 1970 the number of births increased slightly after having declined each year from 1961 to 1968. In 1968, birth rates reached their lowest levels in the past 25 years. During the past decade, the annual birth rates for white women and women of Negro and other races have declined at about the same rate.
   
   It now appears that women born in the early 1930's will complete their childbearing with the highest fertility since women born in the 1880's. Women born in the late 1940's are starting childbearing at a much slower pace than women who were born 10 years earlier, although it is not yet apparent whether the decline reflects changes in the timing of childbearing or changes in eventual completed family size. Both factors may be involved.
2. Age structure and marital status. At present (and for another decade to come), the age structure is becoming more favorable to fertility because the small birth cohorts of the Depression have already passed through the prime childbearing ages and are being replaced with the larger birth cohorts born following the Second World War. The annual number of marriages has increased rapidly during the past few years as these "baby-boom" cohorts have entered the young adult ages. After reaching low points in the late 1950's, the median ages at first marriage for men and women have increased slightly during the past decade.
3. Fertility by social and economic characteristics. Among ever-married women who have nearly completed childbearing (women 35 to 44 years old), Negroes have higher fertility than whites. While a larger percentage of Negro women are childless, a much larger percentage have had five or more children.
   
   Fertility is higher among women living on farms than among women living elsewhere and is lower in metropolitan areas than in nonmetropolitan areas. Fertility is no longer higher in the South than in the remainder of the Nation.
   
   There is an inverse relation between fertility and female labor fo.ce participation and between fertility and family income. Wives of white-collar workers have lower fertility than wives of blue-collar workers.
   
   There is a sharp inverse relation between fertility and educational attainment. Women with only an elementary school education on the average have about one child more than women with a college education. The levels of fertility among white women and Negro women who have completed high school are about the same.
4. Childspacing. Between the late 1940' s and early 1960's, the median number of months between first marriage and first birth and between first birth and second birth declined as women stepped up the pace of their childbearing. (Data for the late 1960's are not yet available.) The interval between first marriage and first birth is longer among women with some college education than among women who did not complete high school.
5. Birth expectations. Between 1955 and 1967, the average number of total children expected by white wives declined slightly suggesting that the recent decline in fertility among young women reflects more than just a change in the timing pattern of fertility. Among wives in the middle childbearing ages (25 to 34), the percent of expected children already born and the percent of wives expecting no more births increased between 1955 and 1967.
   
   On the average, young Negro wives expect to have about the same total number of children as white wives; however, given the much higher fertility to date of these young Negro wives, their expectations may be unrealistically low.
6. Illegitimacy. During the 1960's, the number of illegitimate births increased steadily; however, the increase was due more to the rapid increase in the number of unmarried women in the childbearing ages than to the increase in the rate of illegitimacy among these women. The illegitimacy rate among Negro and other races has declined during the past decade, but is still several times as high as the white rate. At present, more than one- quarter of all births of Negro and other races are illegitimate.
7. Contraception and attitudes toward abortion. The proportion of white wives 18 to 39 years old who had ever used contraception increased between 1955 and 1965. At the latter date, the proportion of wives who had ever used contraception was slightly lower among wives of Negro and other races than among white wives. Within a decade of its introduction, oral contraception had become the most popular method; however, only about one-quarter of all wives in the childbearing ages who had ever used contraception had used oral contraception most recently.
   
   In 1965, the majority of wives under age 55 approved of abortion when pregnancy seriously endangered a woman's health, but disapproved of abortion if the only reason was that a couple did not want any more children. In general, wives with some college education were more favorable toward abortion than wives with an elementary or high school education.