Background: The World Health Organization (WHO) estimates that approximately 350 million new cases of curable sexually transmitted disease (STD) are reported annually in individuals aged 15 to 49 years. Furthermore, the WHO estimates that syphilis during pregnancy causes more than 300,000 fetal and newborn deaths annually and increases the risk of premature death for approximately 215,000 children. In Brazil, more than 100,000 cases were reported during pregnancy between 2005 and 2014. In 2013 alone, approximately 14,000 cases of syphilis in children younger than one year were reported. The present study evaluated the prevalence of syphilis in pregnant women and identified factors involved in the dynamics of disease maintenance.