Risk Factors Associated with Very Low Birth Weight in a Large Urban Area, Stratified by Adequacy of Prenatal Care

Abstract

This study examined risk and protective factors associated with very low birth weight (VLBW) for babies born to women receiving adequate or inadequate prenatal care. Birth records from St. Louis City and County from 2000 to 2009 were used (n = 152,590). Data was categorized across risk factors and stratified by adequacy of prenatal care (PNC). Multivariate logistic regression and population attributable risk (PAR) was used to explore risk factors for VLBW infants. Women receiving inadequate prenatal care had a higher prevalence of delivering a VLBW infant than those receiving adequate PNC (4.11 vs. 1.44 %, p < .0001). The distribution of risk factors differed between adequate and inadequate PNC regarding Black race (36.4 vs. 79.0 %, p < .0001), age under 20 (13.0 vs. 33.6 %, p < .0001), <13 years of education (35.9 vs. 77.9 %, p < .0001), Medicaid status (35.7 vs. 74.9, p < .0001), primiparity (41.6 vs. 31.4 %, p < .0001), smoking (9.7 vs. 24.5 %, p < .0001), and diabetes (4.0 vs. 2.4 %, p < .0001), respectively. Black race, advanced maternal age, primiparity and gestational hypertension were significant predictors of VLBW, regardless of adequate or inadequate PNC. Among women with inadequate PNC, Medicaid was protective against (aOR 0.671, 95 % CI 0.563-0.803; PAR -32.6 %) and smoking a risk factor for (aOR 1.23, 95 % CI 1.01, 1.49; PAR 40.1 %) VLBW. When prematurity was added to the adjusted models, the largest PAR shifts to education (44.3 %) among women with inadequate PNC. Community actions around broader issues of racism and social determinants of health are needed to prevent VLBW in a large urban area.