When is the risk of neonatal transmission for herpes simplex virus highest?

The risk of neonatal transmission for herpes simplex virus is highest when a new herpetic lesion and infection occur near the time of delivery. This is primarily due to the route of transmission during birth. If a mother has an active genital herpes outbreak at the time of delivery, the virus can be passed to the newborn through direct contact with the infected area. This contact can occur as the baby travels through the birth canal, significantly increasing the likelihood of serious complications for the neonate, such as neonatal herpes.

In contrast, acquiring a new herpetic lesion in the first trimester does not pose the same immediate risk during the birth process, as there is a longer time frame for potential antiviral interventions, and the likelihood of lesion presence during delivery is also reduced. Having herpetic lesions around the mouth shortly after birth is not as critical, as this refers to postnatal transmission, which is often less severe than transmission during delivery. Lastly, having herpetic lesions on the genitals throughout pregnancy poses some risk, but if the mother is not experiencing an outbreak at the time of delivery, then the actual risk of transmission during that specific event is significantly minimized. Thus, the timing of the sores and the presence of active lesions at delivery are essential factors in