Background & objectives: Cytomegalovirus, or CMV, is a common virus that infects most people worldwide. CMV infection is usually harmless and rarely causes illness. A healthy immune system can hold the virus in check. However, if a person's immune system is seriously weakened in any way, the virus can become active and cause CMV disease .

Methods: The samples consisted of 120 pregnant women, prospectively screened for CMV by serology from  March 2007 to  September 2007. The women were presenting for routine antenatal care at a tertiary referral women's hospital Maternal ,Children Hospital (M.C.H.) Buridah ,Elqassem, All subjects gave written consent .

CMV IgG and IgM were detected in patient serum by using a commercial microparticle enzyme immunoassay,and determination of the presence of CMV genome by PCR in Amniotic Fluid.

Results: The age range of the pregnant women was 18 to 46 years, with no significant difference seen between the mean age of seropositive and seronegative women.

The CMV seropositivity rate for the pregnant women showed that, overall, 76.8% women were CMV IgG positive at pregnancy.

Pregnant women were considered in high risk due to (i) documented seroconversion to positively for CMV from 3 months before conception to the end of the first trimester of pregnancy (four patients) (ii) CMV symptoms (increase in liver enzyme levels and/or fever) and presence of CMV immunoglobulin M (IgM) (five patients) (iii) intrauterine growth retardation as detected by ultrasound (three patients).

 PCR was used to detect excretion of CMV from the amniotic fluid in 5 of six cases(83.3%) were sero positive,and 1 false negative(16.7%) ,In group without infection  , PCR was positive in 1 case ( 1 false positive ) .

Conclusion: Congenital CMV infection is a major health problem that should be approached on the basis of which women should be enrolled in prenatal diagnostic programs, which clinical specimens should be tested, and which laboratory procedures should be adopted for the diagnosis of congenital CMV transmission or infection. Determination of the presence of CMV genome by PCR in amniotic fluid can be considered as  a rapid ,non invasive and accurate tool for the prenatal diagnosis of congenital CMV infection but negative results cannot rule out of infection ,So that diagnosis of this infection based on correlation between serological and PCR Identification.