Infection with Toxoplasma gondii (T. gondii), when acquired in pregnancy, can lead to fetal infection, which may ultimately result in the loss of the fetus or in lesions involving the brain and the eyes. Rubella, when acquired in the first 12 weeks of pregnancy, is associated with a nearly 90% risk of congenital malformations. The aim of this study was to assess the seroprevalence of T. gondii and rubella among pregnant women at a tertiary referral hospital in central Turkey and to evaluate the use of our results for the prevention of congenital rubella syndrome (CRS) and congenital toxoplasmosis (CT). Data were obtained from the test results of sera collected from pregnant women during their first routine antenatal visit between 2008-2010. The results of the TORCH serology and avidity tests were evaluated. Age-specific subgroups were arranged for the rubella and T. gondii antibodies, and the distribution of seropositivity among the subgroups was assessed. Serum samples were evaluated for rubella (n=31385) and T. gondii (n=30863) IgG, IgM, and IgG avidity. The seropositivity of antibodies for T. gondii was 7869 (25.5%) and 83 (0.3%) for IgG and IgM, respectively. For rubella, the seropositivity was 29478 (93.9%) and 124 (0.4%) for IgG and IgM, respectively. In cases with both IgM and IgG, seropositivity avidity tests were performed. A high avidity of IgG antibodies was detected in 95 (76.6%) rubella cases and 30 (36.1%) T.gondii cases. Seropositivity for T. gondii increased significantly with age, while rubella seropositivity was high in all of the age-specific subgroups. In conclusion T. gondii and rubella are common causes of severe congenital infection. Widespread preventive antenatal measures and screening may help to protect against these teratogenic agents. Due to high seroprevalence of rubella, vaccination programs during childhood and preconceptional periods rather than antenatal screening appear to be more efficient for eliminating CRS. Avoidance of raw meat consumption, proper disposal of the fecal material of domestic animals, and elimination of oocysts from raw food are the main measures to prevent infection with T. gondii. Antenatal screening for toxoplasmosis is warranted, considering the low seroprevalence and serious fetal hazards of congenital infection.