Context . Low birth weight (LBW) is associated with infant morbidity and mortality. This is the first study of LBW in Kansas using vital statistics to determine maternal and health care system factors associated with LBW. Outcomes . Low birth weight. Objective . Determine if prenatal care, maternal socio-demographic or medical factors, or insurance status were associated with LBW. Methods . Birth certificate data were merged with Medicaid eligibility data and subjected to logistic regression analysis. Results . Of the 37,081 single vaginal births, LBW rates were 5.5% overall, 10.8% for African Americans, and 5% for White Americans. Lacking private insurance was associated with 34% more LBW infants (AOR 1.34; 95% CI 1.13–1.58), increased comorbidity, and late or less prenatal care. Low birth weight was associated with maternal medical comorbidity and with previous adverse birth outcomes. Conclusions . Insurance status, prenatal care, and maternal health during pregnancy are associated with LBW. Private insurance was consistently associated with more prenatal care and better outcomes. This study has important implications regarding health care reform.