Americans are having far fewer children than they used to. The crude birth rate has fallen from about 30 births per 1,000 people in 1909 to roughly 12 today — and the trend, interrupted only by the postwar baby boom, points steadily downward. With fertility now below the level needed to replace the population, this is one of the most consequential demographic shifts of our time. This guide charts a century of U.S. birth and fertility rates and explains what's behind the decline.
How much has the birth rate fallen?
The chart tracks two measures: the crude birth rate (births per 1,000 people) and the general fertility rate (births per 1,000 women of childbearing age). Both have fallen by more than half over the past century. The decline isn't a recent blip — it's a long-running trend that stretches back over a hundred years, reflecting the gradual shift from large farm families to smaller urban ones, and the spread of education and contraception.
The baby boom and the bust
The one major interruption to the downward trend is the famous baby boom — the surge in births from the late 1940s through the early 1960s, as returning soldiers started families amid postwar prosperity. It produced the largest generation in U.S. history. But it was temporary: birth rates resumed falling in the 1960s and 1970s as the birth-control pill arrived and women's roles changed, settling into the long, gradual decline that continues today.
Why are Americans having fewer babies?
The reasons are economic and cultural. People marry and have children later, or not at all; the cost of raising children — housing, childcare, education — has climbed; more women pursue higher education and careers; and access to contraception gives families control over timing and size. Recent declines have been steepest among younger women, partly reflecting fewer teen births (a public-health success) and partly a broader trend of delaying or forgoing parenthood.
Below replacement: what it means
U.S. fertility has fallen below the "replacement rate" — the roughly 2.1 children per woman needed to keep a population stable without immigration. Sustained below-replacement fertility means that, over time, deaths begin to outnumber births and the population would shrink and age without immigration to make up the difference. That has profound long-run implications for the workforce, Social Security, and economic growth — which is why birth rates have become a major policy concern.
Frequently asked questions
What is the U.S. birth rate?
About 12 births per 1,000 people today, down from roughly 30 in 1909. The latest figures are shown above.
What is the replacement fertility rate?
About 2.1 children per woman — the level needed to keep a population stable without immigration. U.S. fertility is now below it.
Why is the U.S. birth rate falling?
People have children later or not at all, the cost of raising kids has risen, more women pursue education and careers, and contraception gives families control over family size.
What was the baby boom?
The surge in U.S. births from the late 1940s to early 1960s, as returning soldiers started families in postwar prosperity — the only major interruption to a century-long decline.
What happens if fertility stays below replacement?
Over time deaths outnumber births and the population shrinks and ages without immigration, with major effects on the workforce, Social Security, and economic growth.