Introduction It is estimated that 1.8 million pregnant women worldwide are infected with syphilis and less than 10% are diagnosed and treated. In Brazil, about 30 thousand cases/year with progressive growth are related to social inequalities and lost opportunities of diagnosis and prevention. Considering the importance of a faster detection of this disease, an analysis is necessary because such data could contribute to the development of new syphilis control strategies in this population.

Methods This retrospective case-control study included 170 women (34 cases and 136 controls), where the presence of VDRL and TPHA have defined as a case. The study was based on analyses of medical records of women admitted to the Women’s Hospital Prof.Dr.José Aristodemo Pinotti/Unicamp-São Paulo-Brazil, matched by age over a period of 24 months. Statistical analysis was performed using chi-square and Fisher’s exact tests. For the quantitative variables, descriptive measures were obtained and to verify a significant difference between the mean values, a Mann-Whitney test was used.

Results The prevalence was 1.04% and the mean age was 27.5a. 58.8% of women cases were white, 52.9% with a fundamental education and were in the 3.24 gestation (or 6.77). 70.6% of the controls were white with 45.6% average education and were at 2.27 gestation. In women with syphilis, the average number of sexual partners was 7, the beginning of the sexual activity was 15.3a, 29.5% were drug users (or 0.0001), and 35.3% had a history of STDs. Controls had an average of 2.6 sexual partners, sex at 17.1a, 11.1% used drugs and 7.4% had a history of STDs. The cases had 6.2 consultations (p=0.0664). Half of the partners were not treated. There was 1 neonatal death. Of the 34 women diagnosed with syphilis, only 5 achieved follow-up and cure.

Conclusion A high prevalence of syphilis was identified, which was associated with white, young and multiparous women. Socio-demographic vulnerability and difficulty in diagnosis seem to influence the disease, it is noteworthy that only 1 in 7 women obtained a cure.