Perinatal transmission of human papillomavirus from gravidas with latent infections

Objective: To evaluate the risk of perinatal human papillomavirus (HPV) tra nsmission from mothers with latent infections to the oropharyngeal mucosae of their infants. Methods: Seven hundred eleven mother-newborn pairs were tested. Polymerase chain reaction was done with MY09/MY11 consensus primers to identify HPV DN A in maternal cervicovaginal lavages and newborn nasopharyngeal aspirates. Positive cases were further amplified with type-specific primers for HPVs 6 , 11, 16, 18, and 33. All infants born to HPV-positive mothers were observe d to 18 months for appearance of HPV in oropharyngeal mucosae. Results: Human papillomavirus DNA was detected in 11 neonates born vaginall y to HPV-positive women, a vertical transmission rate was 30% (95% confiden ce interval [CI] 15.9, 47). Nasopharyngeal aspirates were HPV-negative in a ll 11 cases in which rupture of membranes occurred less than 2 hours before delivery. When rupture preceeded delivery by 2-4 hours, and when it occurr ed after more than 4 hours, the respective rates for HPV positivity were se ven of 21 and four of five (chi(2) for trend = 10.7, P =.001). At follow-up , virus was cleared from the oropharyngeal samples as early as the 5th week . Conclusion: Pregnant women with latent HPV infections have low potential of transmitting the virus to the oropharyngeal mucosae of their infants. The time between rupture of the amnion and delivery seems to be a critical fact or in predicting transmission. Human papillomavirus-positive infants should be considered contaminated rather than infected since virus is cleared ove r several months after birth. (Obstet Gynecol 1999;93:475-9. (C) 1999 by Th e American College of Obstetricians and Gynecologists.).