America's Mothers Are Getting Older (2025)
More than one in five U.S. births is now to a mother 35 or older, while teen births have fallen to a historic low.
Key findings
- The average U.S. mother was 29.8 years old at the birth in 2025, and the most common age band was 30 to 34 (30.8% of births).
- More than one in five births (22.0%) was to a mother 35 or older, and 4.3% to a mother 40 or older, the realm once labeled advanced maternal age.
- Teen births have become rare: just 3.5% of births were to mothers under 20, a historic low.
- The distribution has shifted decisively into the 30s, which is also why cesarean, multiple, and preterm rates (all higher at older ages) stay elevated.
American motherhood keeps moving later in life. This takes every 2025 U.S. birth and shows the full age distribution of mothers, the share at 35 and older, and the share who were teenagers. These are exact counts from the near-census of birth records.
Age of mothers, 2025
Births by age of mother
| Category | Share of births |
|---|---|
| Under 20 | 3.5% |
| 20 to 24 | 16.2% |
| 25 to 29 | 27.4% |
| 30 to 34 | 30.8% |
| 35 to 39 | 17.8% |
| 40 and older | 4.3% |
By age group
| Age group | Births | Share |
|---|---|---|
| Under 20 | 127,641 | 3.5% |
| 20 to 24 | 587,564 | 16.2% |
| 25 to 29 | 990,483 | 27.4% |
| 30 to 34 | 1,116,380 | 30.8% |
| 35 to 39 | 642,883 | 17.8% |
| 40 and older | 155,039 | 4.3% |
Mother's age at birth. Exact counts; no sampling margins of error.
Data Sources & Methodology
The figures on this page are computed directly from the source data below. Narrative text accompanies the figures but never generates them.
CDC/NCHS Natality (Births) Public Use File
- Vintage:
- 2025
- Access:
- BigQuery
- Cadence:
- annual
A near-census of U.S. births for the year, drawn from birth certificates. Each row is one birth, carrying the age, education, race and Hispanic origin, and marital status of the mother; prenatal care, pre-pregnancy BMI, and smoking; the delivery method, attendant, birth place, and payer; and the sex, birth weight, gestational age, plurality, and Apgar score of the infant. It supports analysis of who is being born and how, by maternal characteristics.
Every U.S. birth is registered on a birth certificate, which NCHS compiles into an annual public-use micro-file. Each record describes one birth and its mother.
The file covers essentially all registered births in the data year, not a probability sample. Statistics are exact counts; there are no sampling weights and no sampling margins of error.
To protect confidentiality, the public-use file omits state and county. Analyses here are national and by maternal and infant characteristics; state-level figures require CDC WONDER or the restricted-use file.
Gestational age uses the obstetric estimate (combined gestation); birth weight is in grams; delivery method distinguishes vaginal from cesarean; some reported items (education, payer, smoking) carry reporting flags for areas that had not adopted the 2003 certificate revision.
- No state or county geography in the public-use file.
- A few items (for example payer and smoking) were not reported by every area in early revision years; reporting flags identify coverage.
- The final annual file lags roughly a year; provisional counts via CDC WONDER are more timely but less detailed.
- Birth-certificate data depend on accurate completion by hospitals and reporting areas.
How these figures were produced
- Estimate type:
- Administrative near-census (exact counts)
- Weighting:
- None (not a weighted sample)
Suggested citation
Centers for Disease Control and Prevention, National Center for Health Statistics, 2025 Natality Public Use File. Analysis by Matt George, itsmattgeorge.com. Retrieved 2026-10-24.