American women are having fewer babies, but one age group is bucking the overall trend. In 2025, birth rates among women aged 25–29 fell by 4%, while among those aged 30–34 they rose by 3%. Now the age group 30–34 has the highest birth rate in the U.S.

The final statistics, published on October 21 by the U.S. Centers for Disease Control and Prevention (CDC), confirmed a new historic low in fertility. But behind the overall decline hides a much more interesting picture: women under 30 are having fewer children, while birth rates in the age groups from 30 to 44 increased over the past year.

These data reflect a broader shift: American women are gradually delaying childbearing to older ages.

U.S. birth rate reaches a new historic low

According to the final CDC report for 2025, 3,612,012 babies were born in the United States — about 17,000 fewer than the year before.

The general fertility rate fell to 53.2 births per 1,000 women aged 15–44. In 2024, it was 53.8.

Over the year, the rate dropped by 1%, reaching the lowest level on record.

It is important to note that we are talking about a fertility rate, not a record-low absolute number of newborns. This indicator considers how many children are born per 1,000 women of reproductive age.

Preliminary data on the decline were already known in April 2026. Now the U.S. statistical agency has published final figures based on registered births.

The most unexpected finding is the difference between women under and over 30

The overall decline does not mean that fertility fell in all age groups.

Among younger American women, rates continue to fall. In 2025, the birth rate among girls aged 15–19 dropped by 7%, among women 20–24 — by 6%, and in the 25–29 age group — by 4%.

But starting at age 30, the statistics go in the opposite direction.

For women aged 30–34, the birth rate rose by 3%, in the 35–39 group — by 2%, and among 40–44-year-olds — by 1%.

Moreover, the most notable result is related precisely to women aged 30 to 34.

In 2025, there were 85.7 births per 1,000 American women aged 25–29. Among women aged 30–34, the rate was significantly higher — 96.3 births per 1,000.

Thus, the early thirties became the age with the highest fertility rate in the U.S.

However, there is an important nuance: the statistics include all births, including second and subsequent children. This does not mean that most American women become mothers for the first time after age 30.

Age at first birth is also increasing

Other studies also show that women in the U.S. are increasingly postponing childbirth.

According to CDC data, in 2024 the average age of an American woman at first birth reached 27.6 years.

For comparison: in 2016, this figure was 26.6 years.

In just eight years, the average age at first birth increased by about one year.

A similar shift was observed for second and subsequent births. Women became mothers at older ages regardless of the birth order.

Possible reasons for this change are diverse: education, career building, financial stability, housing costs, and changing family preferences.

However, the new CDC report did not investigate the reasons behind American women's reproductive decisions. Therefore, linking the increase in birth rates after 30 to any single factor would be incorrect.

But the rise after 30 is not a simple story

An especially interesting comparison is found in another CDC study, published in April 2026.

Researchers analyzed how fertility rates among women over 30 changed over the previous decade — from 2015 to 2024.

It turned out that among women aged 30–34, the birth rate did not increase over this period—it decreased by 8%.

But in the 35–39 group, it rose by 5%, and among women 40 and older — by a full 24%.

This means that the trend is not uniform even among women over 30.

Therefore, the increase in the rate among 30–34-year-olds in 2025 cannot be considered proof of a new sustainable rise. But long-term statistics do confirm that births are gradually shifting to older age groups.

Why the overall rate still falls

At first glance, the situation seems contradictory: after 30, birth rates are rising, but the country as a whole sets a new historic low.

The explanation is that the positive changes in older age groups do not yet offset the decline in fertility among younger women.

Moreover, percentage changes must be considered together with baseline rates. For example, a 1% increase among women aged 40–44 starts from a much lower fertility level than a 4% decline among 25–29-year-olds.

This also explains why an increase in birth rates per 1,000 women of a certain age does not necessarily lead to an increase in the total number of newborns.

For demographers, such changes are important not only in themselves. They help understand how the age structure of motherhood is changing and which population groups will determine future fertility dynamics.

The new CDC data show that beyond the historic low lies not just a decrease in the number of births. The age profile of motherhood itself is changing: younger women have fewer children, while after 30 the picture becomes completely different.

Based on materials from: CDC — Births in the United States, 2025; CDC — A Decade of Changes in State Fertility Rates for Women Age 30 and Older; CDC — Births and Natality.