Toxoplasmosis is caused by Toxoplasma gondii, which is an intracellular protozoan parasite. Its main host is the cat. It is one of the most common human parasites. The main objective of this study is to determine the time of T. gondii infection among pregnant women by using avidity test of Toxoplasma IgG to various Toxoplasma antigens. The study period was from August 2017 to February 2018 to study the time of toxoplasmosis among 180 pregnant women and 100 non pregnant married women as control attending to hospitals, primary health care centers and some private medical laboratories. The pregnant women were examined for Toxo-IgG seroprevalence by using ELISA technique, and then examined their avidity of antibodies for specific Toxoplasma antigens by using line immune assay. The rates of Toxo-IgG seropositive were64 (35.56 %) among pregnant women. Regarding the reactivity of determined Toxo-IgG against various Toxoplasma antigens, the rates were 40(62.50%), 39 (60.93%), 63(98.43%) ,55(85.93%) ,63(98.43%), 62(96.87%) ,41(64.04%) and 42(65.62) positive for Toxoplasma ROP1C, MIC3, GRA7, GRA8, p30, MAG1,GRA1,rSAG1 antigens, respectively. Considering the avidity of Toxo-IgG for these antigens, the rates of high avidity were higher than low and intermediate avidity. So, the highest rate of high avidity was 85.0% for ROP1c antigen. It is concluded that the highest rate of predicting Toxoplasma infection among pregnant women was for a period of more than 6 months, which makes it less dangerous for maternal and fetal health..