Objective:The goal of the present study is to highlight the significance of the determination of IgG avidity to herpes simplex2virus(HSV2) compared to detection of viremia by polymerase chain reaction(PCR) in relation to recurrent abortions.Methods:Serum samples from pregnant patients with bad obstetric histories and control subjects were analyzed for quantitative determination of IgG specific for HSV2 by using ELISA with and without sample treatment with 8 M urea as protein-denaturing agents for measurement of avidity index(AI).PCR was performed for samples to determine HSV2 viremia.Results:Regarding avidity index 11.5%had avidity index = 100.0,11.5%has avidity index = 47%and 76.9%had avidity index>60%.Control group had AI>70%.There was statistically insignificant difference between OD of IgG in patients with viremia before urea treatment and after urea treatment compared to healthy control.Also there was statistically insignificant difference in OD before urea and after urea in patients with viremia.Conclusion:From this study we can conclude that viremia for HSV2 is common finding in patients with bad obstetric history.Low avidity immunoglobulin G was not common finding in those patients.This may be explain that even reactivation of latent HSV 2 infection is associated with fetal loss. Objective: The goal of the present study is to highlight the significance of the determination of IgG avidity to herpes simplex2 virus (HSV2) compared to detection of viremia by polymerase chain reaction (PCR) in relation to recurrent abortions. Methods: Serum samples from pregnant patients with bad obstetric histories and control subjects were analyzed for quantitative determination of IgG specific for HSV2 by using ELISA with and without sample treatment with 8 M urea as protein-denaturing agents for measurement of avidity index (AI). PCR was performed for samples to determine HSV2 viremia.Results: Regarding avidity index 11.5% had avidity index = 100.0,11.5% has avidity index = 47% and 76.9% had avidity index> 60% .Control group had AI> 70% .There was statistically insignificant difference between OD of IgG in patients with viremia before urea treatment and after urea treatment compared to healthy control. Also there was statistically insignificant difference in OD before urea and after urea in patie nts with viremia.Conclusion: From this study we can conclude that viremia for HSV2 is common finding in patients with bad obstetric history. Low avidity immunoglobulin G was not common finding in those patients. This may be explained that even reactivation of latent HSV 2 infection is associated with fetal loss.