Aim This article aims to evaluate access to prenatal care according to the dimensions of availability, affordability and acceptability in the SUS microregion of southeastern Brazil. Methods A cross-sectional study conducted in 2012-2013 that selected 742 postpartum women in seven hospitals in the region chosen for the research. The information was collected, processed and submitted to the chi-square test and the nonparametric Spearman's test, with p-values less than 5% (p < 0.05). Results Although the SUS constitutionally guarantees universal access to health care, there are still inequalities between pregnant women from rural and urban areas in terms of the availability of health care and among families earning up to minimum wage and more than one minimum wage per month in terms of affordability; however, the acceptability of health care was equal, regardless of the modality of the health services. Conclusion The location, transport resources and financing of health services should be reorganised, and the training of health professionals should be enhanced to provide more equitable health care access to pregnant women.