Effects of Medicaid eligibility expansion on prenatal care and pregnancy outcome in Tennessee.

To investigate the effects of a 1985 Tennessee Medicaid regulatory change that expanded eligibility coverage specifically for married women during pregnancy, we studied vital statistics files linked to Medicaid enrollment files. The greatest Medicaid coverage increase in terms of an absolute difference in rates and the number of women covered occurred in white married women younger than 25 years with less than 12 years of education, where enrollment increased 18%. However, in that group of mothers, as well as for the total of all mothers studied, there were no concomitant improvements in use of early prenatal care, birth weight, or neonatal mortality. Analysis of the timing of enrollment relative to the beginning of pregnancy showed that more than two thirds of the women who enrolled did so after the first trimester.