Perinatal transmission and maternal risks of human papillomavirus infection.

We conducted a prospective study to investigate whether human papillomavirus (HPV) could be vertically transmitted to neonates. Pregnant women (N = 203) were tested for HPV DNA infection during the third trimester and again during labor prior to delivery. Their newborns (N = 203) were tested 1 to 3 days after delivery. Among the mothers, 12.3% (N = 25/203) typed HPV positive at either or both maternal specimen collection periods, whereas only 1.0% of the neonates (N = 2/203) typed positive. This low transmission rate may be due in part to the fact that 65% of mothers who were HPV positive during the third trimester tested HPV negative by labor/delivery. The higher frequency of risks associated with maternal HPV infection were similar to those found in studies of cervical dysplasia and cancer: younger age at first intercourse and first pregnancy, number of sexual partners, and longer duration in use of oral contraceptives. In addition, those who were past smokers and had a shorter recency and latency period in smoking were more likely to be detected with HPV.