Aim of the study was to investigate serological markers of selected sexually and blood transmitted infections (HBV, HCV, CMV, and Treponema pallidum) in the group of pregnant women and in newborns of HIV-positive mothers in Slovakia. IgG antibodies to CMV were found in 78 of 97 women, from them in 6 of 7 HIV-positive and in 72 of 90 HIV-negative persons. Occurrence of HbsAg and HCV was significantly higher in the group of HIV-positive women (1/7 and 2/7) comparing to the HIV-negative one (4/90 and 0/92, respectively). Antibodies to T. pallidum were found only in one HIV-negative woman from 92 women tested. Five of seven children born to HIV-1 infected mothers were found HIV-1 negative, two children are still under control. Four of 7 newborns were found anti-CMV IgG positive. Although one woman, IDU, was confirmed HbsAg and anti-HCV positive, vertical transmission of HBV and HCV to her newborn was not observed by molecular-biological methods. Similarly, HCV antibodies were found in one more women and neither in her child HCV infection was confirmed. In no one of mother - child pair's antibodies to T. pallidum were observed. Due to these findings strong attention should be paid to health education and prophylaxis of mother to child HIV and other STIs transmission in Slovakia.