To estimate health care costs of live births and the impact of prenatal care visit (PCV) in women from poor households.A randomized sample of 9 244 pregnant women (out of total= 25 000). Mean differences and proportions were calculated to compare results in both groups of women. The costs were estimated in American Dollars (USD) 2014, from the payer's perspective.75% of women live in urban areas. The mean age was 23 years old (CI95% 23.5-23.8). The average cost with PCV was USD 609.1 (CI95%: 581-632.7) and without PCV was USD 857.8 (CI95%: 774.7-923.8) and 87% of women attended at least one PCV. The health care costs increased in 32% (CI95% 27.1-41) in women who did not attended PCV.The PCV is an efficient and effective intervention for managing the risk of maternal health.