Rates of first trimester prenatal care were 47.3% for women in the Medicaid GAP, 70.0% for women who were not. The adjusted odds ratio for being in the Medicaid GAP and delayed prenatal care was 2.7 (95% CI 1.2, 6.2), although this varied by race/ethnicity and education. The relationship was strongest among White and Hispanic women with less than a high school education: OR=13.8, (95% CI 3.0, 62.7) and OR=19.0 (95% CI 2.4, 149.2), respectively.