Prevalence of herpes simplex virus types 1 and 2 at maternal and fetal sides of the placenta in asymptomatic pregnant women

Problem Herpes simplex virus 1 (HSV-1) commonly causes orolabial infection, but can also infect the genital mucosa. In contrast, HSV-2 is usually genital. Genital herpes can transmit the virus vertically to the fetus during pregnancy. We sought to estimate the prevalence of HSV-1/2 on the maternal and fetal sides of the placenta. Method of study Placental tissues were collected from pregnant women seen at the Rio Grande University Hospital. HSV-1 and HSV-2 were detected by nested PCR. Results The prevalence of HSV-1 and HSV-2 was, respectively, 28% and 12.6% (maternal side) and 29.9% and 8.3% (fetal side). All HSV-positive women were asymptomatic. Sexual behavior, vaginal delivery, and presence of HSVs on one side of the placenta were risk factors associated with HSV infection. Conclusion The occurrence of HSVs in placental tissue was high, especially for HSV-1. Novel strategies need to be implemented for the management of asymptomatic women who might transmit HSV to their newborns.