Low prenatal weight gain among low-income women: what are the risk factors?

Although a large body of evidence suggests that prenatal weight gain is an important determinant of fetal growth, 23 to 38 percent of nonobese women have low prenatal weight gain. Determination of potential risk factors for low gain is essential to develop targeted intervention programs. This study examined the association of maternal sociodemographic, lifestyle, and reproductive characteristics with the actual occurrence of low gain among 536 black and 270 white low-income, nonobese women.

Sociodemographic, pregnancy wantedness, reproductive, and anthropometric data were obtained by interview during the first prenatal visit. A 72-item questionnaire, administered at 24 to 26 weeks' gestation, assessed residential and household characteristics, housing characteristics, income, transportation, physical activity, employment, and institutional support. Variables associated with low gain in bivariate analyses were included in logistic regression analysis to determine the adjusted odds ratios for low gain.

Three characteristics were associated with increased adjusted odds ratios for low prenatal weight gain among black women: having a mistimed or unwanted pregnancy, caring for more than one preschool child at home, and not using own car for errands. One characteristic, working more than 40 hours per week when employed, was associated with low gain among white women.

Although these preliminary findings require additional confirmation, they suggest that a variety of sociodemographic and lifestyle features deserve investigations that target the identification and characterization of risk factors for low prenatal weight gain.