What percentage of live births yearly in the United States are premature?
Of the 4.2 million babies born in the United States in 2008, 12.3% were premature. (A baby born at 37 weeks is considered premature. Normal gestation is 39 weeks.)
Blacks have a higher rate of premature births than the general population; the premature-birth rate for non-Hispanic Blacks in 2008 was 17.5% of all births.
—The Fact Monster