Effects of short interpregnancy intervals on small-for-gestational age and preterm births.
We examined the effects of short interpregnancy intervals on small-for-gestational age and preterm births in a biracial population using North Carolina birth certificate data from 1988 to 1994. We defined small-for-gestational age birth as being below the 10th percentile on a race-, sex-, and parity-specific growth curve after a gestation of 37-42 weeks. We defined preterm birth as a gestation of less than 37 weeks. We analyzed birth records from all eligible singleton births to black or white women ages 15-45 years after an interpregnancy interval of 0-3 months (N = 11,451) and a random sample of singleton births after an interval of 4-24 months (N = 23,118). We defined interpregnancy interval exposure categories as 0-3, 4-12, and 13-24 months. The multivariate adjusted odds ratio for small-for-gestational age births after interpregnancy intervals of 0-3 months compared with 13-24-month intervals was 1.6 (95% confidence interval = 1.4-1.8). The odds ratio for preterm birth after interpregnancy intervals of 0-3 months was 1.2 (95% confidence interval = 1.1-1.3). Odds ratios did not vary substantially by race for either outcome.
Shults
R A
RA
Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill, USA.
Arndt
V
V
Olshan
A F
AF
Martin
C F
CF
Royce
R A
RA
D000293:Adolescent; D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data*; D001721:Birth Intervals; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D016015:Logistic Models; D008875:Middle Aged; D015999:Multivariate Analysis; D009657:North Carolina / Q000453:epidemiology; D007752:Obstetric Labor, Premature / Q000208:ethnology* / Q000209:etiology*; D011159:Population Surveillance; D011247:Pregnancy; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects / Q000208:ethnology; D012959:Socioeconomic Factors; D044465:White People / Q000706:statistics & numerical data*