Congenital syphilis (CS) is a preventable epidemic disease for which control is hindered by socioeconomic and health system issues. Inadequately treated maternal syphilis (MaS) commonly has serious adverse obstetric outcomes. This study – which is a cross-sectional study in a Brazilian large urban public Mother and Child hospital, making use of secondary data – evaluated the occurrence of treatment of sexual partners (SP) among women with MaS. The results showed that 771 MaS cases were identified from 2007 to 2014. No information on SP treatment was available in 570 (73.9%) cases. Of the 201 cases presenting information, 25 (12.4%) SP were treated. Out of 164 women having six or more prenatal visits, 25 (15.2%) SP received treatment. Data analyzed biennially have shown a growing trend of cases without collected information, ranging from 27.2% in 2007–2008 to 87.5% in 2013–2014. No linear trend in proportions of treated SP (maximum 7.4% SP treated) was found. Thus, in this study, it has been concluded that the proportion of SP adequately treated was consistently low, and the quality of information deteriorated during the studied period. Prenatal care per se, as provided, was not effective in delivering adequate treatment of SP. Creative integrated services with SP active participation are greatly needed if CS is to be controlled.