Prevalence of Low Birth Weight and Preterm Delivery in Relation to the Interval Between Pregnancies Among White and Black Women

Abstract

Background The higher mortality rate among black infants than among white infants in the United States results largely from the greater frequency of low birth weight and prematurity among black infants. Higher rates of low birth weight and preterm delivery have been associated with shorter intervals between pregnancies. Methods We studied a racially mixed population of women in military families, who had access to free, high-quality health care. A total of 1922 white and black women had two consecutive, singleton pregnancies during the study period. We determined the outcome of the second of each pair of pregnancies and the length of time between the pregnancies. Results Short interpregnancy intervals (calculated from delivery to the next conception) were more frequent among black than among white women. A total of 7.7 percent of the 298 black women and 3.2 percent of the 1628 white women delivered premature, low-birth-weight infants (P<0.001). Among the black women, an interpregnancy interval of less tha...