Absence of cytomegalovirus in gestational tissue in recurrent spontaneous abortion

There have been conflicting reports regarding the association of cytomegalovirus (CMV) and recurrent spontaneous abortions. It is difficult to assess the role of CMV in the endometrium by histology alone, since the characteristic cytomegalic virocytes are often scarce or absent in this site. Our purpose was to use the polymerase chain reaction (PCR) to detect cytomegalovirus in gestational tissue of women with recurrent spontaneous abortions. DNA was extracted from 25 samples of paraffin-embedded, formalin-fixed gestational tissue from 21 women with at least three unexplained spontaneous abortions (mean, 3.4). DNA from an unstained paraffin section of each specimen was amplified using nested, multiplex PCR specific for the late antigen and the major immediate early genes of CMV. The assay used has a demonstrated level of sensitivity on the order of 10(-2) virocytes per square centimeter of 4-microM paraffin section. Intact DNA was successfully isolated from 21 specimens in 18 patients. Histologic features of CMV infection were completely absent from these cases, and none of these specimens contained evidence of cytomegalovirus DNA. These findings suggest that CMV infection of gestational tissue is not a common direct cause of recurrent spontaneous abortions.