Template:USA Preterm Birth Rate table
From Embryology
| Class | Age | Rate (per 100 births) |
|---|---|---|
| Total preterm | less than 37 weeks’ gestation | 12.7 |
| Extremely preterm | less than 28 weeks’ gestation | 0.8 |
| Early preterm | less than 34 weeks’ gestation | 3.6 |
| Late preterm | 34–36 weeks’ gestation | 9.0 |
| Data: USA Preterm birth rates national Vital Statistics System, United States, 2007. | ||
