Human herpesviruses 6 and 7 in cervixes of pregnant women.

We looked for human herpesvirus 6 (HHV-6) and HHV-7 genomes in the cervixes of pregnant women in the late stages of their pregnancies. Of 72 samples collected with cervical swabs and amplified by nested PCR, we found that 14 (19.4%) and 2 (2.7%) contained detectable HHV-6 and HHV-7 genomes, respectively. The two samples in which HHV-7 DNA was detected also contained HHV-6 genomes. Hybridization of HHV-6 DNA amplified by PCR with variant-specific probes revealed that all of these DNA samples belonged to variant type B. These results indicated that HHV-6 and/or HHV-7 exists in the cervixes of infected women in late pregnancy and may cause perinatal infection.