Objectives: to investigate the information received by pregnant women considering assistance care and educational factors on syphilis and its association with the diagnostic of congenital syphilis in a referral maternity. Methods: a case-control study conducted in a referral maternity in Minas Gerais, Brazil, from 2017 to 2018. A case group included newborns’ mothers with presumptive congenital syphilis and A control group was considered healthy newborns ’ mothers. Clinical, obstetrics variables and information about maternal educational approach on syphilis during prenatal care were obtained through interviews and medical records. Descriptive and comparative analyses were performed. Chi-square or Fisher's exact test and odds ratio were calculated followed by multivariate logistic regression. Results: sixty mothers were included in the case group and 120 mothers in the control group. Mothers in the case group presented lower schooling level and they were 24 times more likely to have information about the risks of congenital syphilis and five times more likely to had received previous treatment for syphilis and mothers in the control group were 10 times more likely to receive information about Sexually Transmitted Infections during prenatal care. Conclusion: adequate health assistance identifying previous history of syphilis and health education improving its information about Sexually Transmitted Infections can help prevent congenital syphilis, which indicates the necessity of a better approach by the professionals during prenatal care.