Perinatal infections account for 2-3% of all congenital anomalies. TORCH which includes Toxoplasma, Rubella, Cytomegalovirus & Herpes Simplex virus, are some of the most common infections associated with Congenital anomalies. Most of the TORCH infections cause mild maternal morbidity, but have serious fetal consequences. Reliable recognition of acute infection is highly important in pregnant women. IgM-positive result alone does not accurately predict the risk of fetal infection; a positive IgM test should therefore be considered only as a starting point and a more thorough diagnostic evaluation is necessary to determine whether there is a risk of fetal infection. Primary CMV infection may result in establishment of persistent or latent infection. Infections can be acquired through direct contact with individuals shedding the virus. Once HSV infection occurs, it persists in a latent state in sensory ganglia from where it may re-emerge to cause periodic recurrence of infection induced by many stimuli, which may or may not result in clinical lesions. Demonstration of Toxoplasma IgG in the serum of person with eye lesion helps in diagnosing Ocular toxoplasmosis while persistent or increasing IgG antibody levels in the infant compared with the mother and/or positive result of Toxoplasma specific IgM or IgA are diagnostic of Congenital toxoplasmosis. Demonstration of rising antibody titer (four fold) in acute and convalescent sera taken 2-3 weeks apart is indicative of postnatal Rubella infection and helps to check response to Rubella vaccination. Single test results of CMV IgG are useful in screening organ transplant recipients and donors before transplantation and donors of blood products that are to be administered to premature infants and bone marrow transplant patients. Positive result of HSV (1+2) IgG indicates past infection with Herpes Simplex virus or administration of HSV immunoglobulins. Reliable recognition of acute infection is highly important in pregnant women.