A probability sample survey of high-risk inner-city women with a live birth in the last 3 years shows that maternal medical risks and health behaviors during pregnancy are important intermediate variables influencing preterm delivery and birthweight. Women who developed two or more medical risks had about three-and-a-half times the risk of preterm delivery and two-and-a-half times the risk of low birthweight compared to those without such risks. Women with prior fetal loss had twofold increase in the risk of preterm delivery and low birthweight. Unintended pregnancy resulted in one-and-a-half to twofold increase in preterm delivery and low birthweight, respectively. Inadequate gestational weight increased the risk of preterm delivery by about 50%. Smoking during pregnancy raised the risk of low birthweight slightly more than one-and-a-half times.
PIP: A probability sample survey of 1004 women from Pittsburgh, Pennsylvania, who had a live birth in the preceding three years indicated that the impact of poverty on pregnancy outcome is mediated by maternal medical risk factors and health behaviors during pregnancy. Study subjects were predominantly Black and drawn from inner-city areas with high poverty rates. None of the sociodemographic or economic variables included in the analysis (e.g., maternal age, race, household income, education, and marital status) was a significant predictor of the two adverse pregnancy outcomes considered: deliveries under 37 weeks' gestation and birth weights under 2500 g. Women with two or more medical problems during pregnancy had a 3.5 times greater risk of preterm delivery and twice the risk of low birth weight than those with no such problems. There was a two-fold increase in the risk of both adverse outcomes among the 22% of respondents who had experienced a prior pregnancy loss. Among the 54% of respondents who indicated the most recent pregnancy was unwanted, the risk of these outcomes was increased by 1.5-2.0 times. Maternal weight gain during pregnancy of less than 25 pounds was associated with a two-fold increase in low birth weight, while smoking during pregnancy increased this risk by 1.6 times.