Twins, Triplets, and Maternal Age (2025)
About one in thirty-three U.S. births is a multiple, the odds climb with the mother's age, and three in four twins are delivered by cesarean.
Key findings
- About one in 33 U.S. births was a multiple in 2025: 30.4 per 1,000 births, or 107,568 twins, 2,254 triplets, and 105 higher-order births.
- The multiple rate rises steadily with the mother's age, from 21.8 per 1,000 among mothers under 25 to 35.3 per 1,000 among mothers 40 and older.
- Older maternal age and fertility treatment both raise the odds of twins, which is a big reason multiples cluster in the 30s and 40s.
- Multiples are delivered very differently: 74.5% of multiple births were cesarean, versus 31.1% of single births.
Twins and triplets are rare, but who has them is far from random. This measures the multiple-birth rate for every 2025 U.S. birth, how it climbs with the mother's age, and how differently multiples are delivered. These are exact counts from the near-census of birth records.
Multiple births, 2025
Multiple-birth rate by mother's age
| Category | Multiples per 1,000 births |
|---|---|
| Under 25 | 21.8 /1k |
| 25 to 29 | 29.1 /1k |
| 30 to 34 | 33.4 /1k |
| 35 to 39 | 35.4 /1k |
| 40 and older | 35.3 /1k |
By mother's age
| Mother age | Multiples per 1,000 |
|---|---|
| Under 25 | 21.8 |
| 25 to 29 | 29.1 |
| 30 to 34 | 33.4 |
| 35 to 39 | 35.4 |
| 40 and older | 35.3 |
Multiples are twin and higher-order births (plurality 2 or more). 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.