The U.S. birth rate has once again hit an all-time low, raising fears that the population replacement line is collapsing. As the timing of childbirth is clearly shifting into the 30s and beyond, analysts say even the minimum threshold for maintaining the population is under threat.
According to the National Center for Health Statistics (NCHS) under the Centers for Disease Control and Prevention (CDC), the U.S. birth rate in 2025 (number of births per 1,000 women ages 15–44) was 53.1. That was down 0.7 from the previous year's 53.8, the lowest level since the data have been collected. Total births the same year were 3,606,400, down 1% from the previous year.
The U.S. birth rate has been on a steady decline since 2007, when the millennial generation began entering their prime childbearing years. The New York Times (NYT) called it a "demographic mystery," noting that various explanations are being offered for the continued downturn.
◇ Teens and 20-somethings fell, while those in their 30s rose
The most notable change is the "shift in childbearing age." While birth rates among teens and people in their 20s are falling rapidly, those among people in their 30s and 40s are rising. Last year, the birth rate for women ages 15–19 was 11.7, down 7% from the year before. The teen birth rate has steadily declined since peaking in 1991. The birth rate among those in their 20s also continued to fall. The Wall Street Journal (WSJ) analyzed the shift as a postponement of births rather than a disappearance.
Recently, the birth rate for women in their late 30s has even surpassed that of women in their early 20s. The center of childbirth is moving from the 20s to the 30s and beyond.
◇ Why are people in their 20s having fewer babies and those in their 30s having more?
Experts interpret this not as a "decline in childbirth" but as a "delay in childbirth." In reality, many women are not giving up on having children altogether but are pushing back the timing.
The biggest reason is financial burden. Housing costs, child-rearing expenses, and student loans overlap, making it difficult to decide on childbirth in one's 20s, analysts say. There is a clear tendency to consider having children only after securing a stable job and income. Later marriages also play a role. Rising average ages at first marriage and concerns about relationship stability are pushing back the timing of childbirth as well.
Wendy Manning, a professor at Bowling Green State University, said, "People are delaying when they become parents," adding, "There is a strong tendency to make sure the foundation of life is stable."
Some analysts say past policies aimed at reducing teen births have also had an impact. Karen Guzzo, director of the Population Center at the University of North Carolina, said, "The United States has long discouraged early childbirth," and explained, "The perception that having children early is not desirable has taken root across society."
◇ "If you have children later, you ultimately have fewer"
The problem is that delaying childbirth is highly likely to lead to fewer births in the end. The longer childbirth is postponed, the fewer children people tend to have.
According to the NYT, 37% of the decline in the U.S. birth rate from 2007 to 2019 stemmed from reductions in birth rates among Black, Hispanic, and white teenagers. A decrease in the birth rate among white women ages 20–24 without a bachelor's degree also had a significant impact on the overall decline.
The U.S. population is still growing, but the pace is slowing. That is the result of low birth rates and reduced immigration acting at the same time.
Some experts warn that if the delay in childbirth becomes prolonged, it may be difficult to restore the soundness of the population structure. If the trend of postponing childbirth hardens, they say, population decline will be hard to avoid.