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[Detection of intrauterine transmission of human cytomegalovirus by nested polymerase chain reaction].

OBJECTIVE
Using nested polymerase chain reaction (PCR) to detect Intrauterine transmission of human cytomegalovirus (HCMV).


METHODS
Ninety one cases of pregnant women were devided into three groups according to their gestational stages. In the first and second trimesters, they terminated pregnancy voluntarily. HCMV-DNA in maternal and cord blood as well as placenta were detected respectively by nested PCR.


RESULTS
In the first trimester, 20 out of 30 cases were infected, Intrauterine transmission occured in 8 of the 20 infected mothers (HCMV-DNA were found in the chorionic villus). In the second trimester, 21 out of 30 cases were infected, 7 of them transmitted HCMV to their fetus through placenta. In this term, the placenta infection rate is 40% (12/30). In the third trimester, 23 out of 31 cases women infected HCMV, 18 of them transmitted HCMV to their fetus through placenta, the placenta infection rate is 66.67% (20/30). The congenital infection rate is 58.06% (18/31), much higher than the reported levels marked by cord sera IgM and (or) infants viremia.


CONCLUSIONS
HCMV transmitted from mother to infant mainly through placenta. Nested PCR provides a valuable method that can detected virus infection not limited by virus reproduction state and human immuno-reaction ability.