More older women becoming first-time moms amid U.S. fertility rate declines

NBC News

18-03-2025

Amid growing evidence of slowing fertility rates in the United States, a new report contained a pair of surprising details from two divergent age groups: A growing number of women older than 40 are having children and a record low number of teenagers are giving birth.
The report, released earlier this month by the National Center for Health Statistics (NCHS), showed that the U.S. fertility rate — the average number of children born to a woman during her reproductive years — continued its decadeslong slide through 2023, with American women having an average of 1.62 children, compared to 1.66 in 2021 and 2022.
Overall, the rate has declined 14% since 1990, driven largely by younger women under the age of 30 who are having fewer children.
For the first time in 2023, there were more births among women 40 and older than there were to teenage girls, a trend which aligns with both long-sought public health goals of decreasing teen births, while reflecting medical advancements which have allowed older women to have healthy pregnancies.
'There's a flip in the age distribution,' said Elizabeth Wildsmith, a family demographer and sociologist at Child Trends, a nonpartisan research group.
In 1990, adolescents accounted for almost 13% of all births; in 2023, they made up 4%. And most critically, the fertility rate for girls ages 10 to 14 dropped from 1.4 to almost zero, something Wildsmith called 'a success story' from a public health perspective.
At the same time, demographers are still trying to discern why women are choosing to become pregnant and give birth later. The most recent data show that most births now occur to women ages 30 to 34, while a decade ago the cohort that was most likely to give birth was 25 to 29.
As the average maternal age has increased, far more women ages 35 and older are also having children, according to the NCHS, part of the Centers for Disease Control and Prevention which tallies all known births in the U.S. From 1990 to 2023, the fertility rate for women ages 35 to 39 increased 71%, and for women ages 40 to 44, the rate increased 127%.
Researchers say that there are a number of possible explanations for the gradual increase in the age of new mothers, including evolving social expectations and values; changes in technology and dating behavior; the economic burden of child rearing; and increasing college enrollment among women.
'All of those conditions shape when people want to start having children,' said Wildsmith, who also noted that when 'women are able to control their fertility,' other opportunities — including professional, political and economic — become easier to access.
Teen births drop sharply
While the national decline in teen births has been hailed by public health officials, that decrease has not been uniform across all states, according to federal data. Southern states from West Virginia to Texas have higher rates of teen births than other regions, and the teen birth rate in Mississippi, Arkansas and Louisiana is double that of the national rate.
In Mississippi, for example, 53% of high school students did not use a condom the last time they had sex, according to a state youth risk behavior survey. Teen mothers are less likely to complete high school and, in Mississippi, about half of teen girls who give birth receive a high school diploma.
Still, the teen birth rate in Mississippi has dropped precipitously from 46.1 in 2012 to 23.6 in 2021, according to state data.
Dr. Samuel Jones, a family practice physician and the clinic director at the student health center at Jackson State University, said students can receive free or low-cost contraceptives, including birth control pills and long-acting methods such as injections and patches.
'We are advocates for healthy children,' he said. 'Unplanned pregnancies may have an effect on our college students. They are career bound, and many are dating for the first time.'
Jones, who has practiced family medicine long enough in Mississippi that patients he knew as children are now parents themselves, says longer term contraceptives, including Depo Provera, an injectable long-acting birth control, have proved popular with teen patients -- and their parents.
'The pills were somewhat problematic because the dropout rate was higher,' he said, adding that routine shots of Depo Provera give many parents peace of mind that their children will be protected from unplanned pregnancy.
The Affordable Care Act, signed by then-President Barack Obama in 2010, ushered in a new era of teen pregnancy prevention. The federal law required that preventative health care, which included all contraceptive products, be included with no co-pays or deductibles.
States with the lowest teen birth rates include New England, Minnesota, New Jersey, New York, Utah, Washington, California and Wisconsin, where there seems to be a connection between lower rates and comprehensive sex education, said Dr. Aisha Mays, founder of the Dream Youth Clinic in Oakland, California, and a clinical researcher with the UCSF Bixby Center for Global Reproductive Health. Elements of those programs include medically accurate education about fertility anatomy, contraception, sexual consent and sexual readiness.
And just as vital for teens, she said, is insurance coverage and access to contraception without parental consent 'so that young people can talk freely with a medical provider.'
Complications may increase with age
While many women become pregnant without medical intervention, advances in reproductive technology and expanded insurance coverage for fertility preservation and treatment have allowed women and couples to 'prioritize their career and life goals,' said Dr. Arianna Cassidy, a maternal-fetal medicine specialist at University of California, San Francisco.
The risk of various pregnancy and fetal complications increases incrementally for women over age 35, she said. That includes the risk of certain genetic and chromosomal abnormalities including Down syndrome, and the risk of pre-eclampsia, gestational diabetes and postpartum hemorrhage.
'There's not a switch that goes on at age 35 where all these things are going to happen, it's more of a continuum,' she said.
Some of those risks can be mitigated with proactive medical care such as taking baby aspirin during pregnancy for those with risk factors for pre-eclampsia; prescribing medication to control blood pressure and gestational diabetes; and better awareness about the dangers of postpartum hemorrhage.
Adverse outcomes are still rare. The risk of pre-eclampsia, a dangerous hypertensive disorder that is poorly understood but remains a leading cause of maternal and perinatal mortality worldwide, is less than 5% among the general population of pregnant women.
Among women older than 40, Cassidy said, the risk doubles to about 10%.
'We're seeing more and more people who come into pregnancy in their 40s who already have high blood pressure, kidney disease or diabetes,' she said. 'Age is not a modifiable thing.'