Introduction The increase in congenital syphilis rates represents near-failure to the usual public health resources, making room for new approaches such as the inclusion of the partner in prenatal care. To evaluate the influence of this new strategy ”Male Partner in the Prenatal Care Strategy (MPPCS)” on: 1) The vertical transmission (VT) rate of syphilis; 2) The syphilis rate among pregnant women; 3) The syphilis rate in the partners who joined the strategy; 4) What variables influence partner`s adherence in the MPPCS.

Methods This was a longitudinal study carried out in Ribeirao Preto (São Paulo State, Brazil). It was enrolled pregnant women (PW) and live births (LB) divided in two groups. The group in which had their partners participating in the MPPCS project was denominated PW1 and LB1, and the group without participation in the MPPCS project was denominated PW2 and LB2. These groups were followed from beginning until the end of pregnancy. Were selected 5391 pregnant women (1781 of the PW1 and 3610 of the PW2), and 4044 LB (1376 of the LB1 and 2668 of the LB2). The statistical analyses were done by Chi-square test of Pearson with a 5% significance level.

Results The results showed that VT rates of syphilis were lower in the group where the partners have adhered to the MPPCS. The VT rate found were: 0.7% in LB1% and 1.5% in LB2 (p=0.04). The syphilis rate found in the partners participating in the MPPCS was 1.3%. In the pregnant women, there was no association between the occurrence of syphilis between PW1 (1.6%) and PW2 (2.0%), with p=0.20. The main variable that have influenced partner`s adherence rate in the MPPCS project was the commitment of the health care team, with some units presenting 98% of partner’s adhesion and others with less than 20%.

Conclusions The adherence of partners in the MPPCS was very important in the identification and treatment of male-pregnant women with syphilis, and significantly reduced the TV rate of syphilis. The commitment of the health care team is the most important variable in the adherence of the partner to the MPPCS.