Presents as painful vesicles on an erythematous base that evolve into shallow open ulcers or erosions. Maternal HSV infection can cause neonatal infection, which can be devastating due to significant morbidity (eg, seizures, developmental delay, blindness) and mortality.
Common neonatal complications of HSV infection include vesicular skin lesions and ocular involvement, while neonatal encephalitis is a potential severe complication of the infection. Maternal herpes simplex infection does not cause fetal malformations; rather, it can cause fetal infection if the newborn comes into contact with herpetic lesions during delivery.
<aside> 💡 beginning at 36 weeks gestation until delivery, pregnant women with a history of genital HSV receive antiviral prophylaxis (eg, acyclovir, valacyclovir) regardless of symptoms
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HSV can be vertically transmitted transplacentally (typically with a primary infection); however, the most common route of transmission is during vaginal delivery because the fetus is exposed to HSV during passage through the birth canal. The risk of transmission is proportional to the amount of viral shedding, which is highest during prodromal symptoms and active lesions. Therefore, patients with either prodromal symptoms or active genital HSV lesions at delivery (eg, active labor, as in this patient) cannot undergo vaginal delivery and require an immediate cesarean delivery.
In contrast to this patient, individuals who have a history of genital HSV but have no prodromal symptoms or active lesions at delivery can undergo vaginal delivery because maternal viral shedding and the risk of vertical transmission are minimal.
Women who have a history of genital HSV receive prophylactic antiviral therapy (eg, acyclovir, valacyclovir) from 36 weeks gestation until delivery to reduce the risk of active lesions at delivery and the need for cesarean delivery. In contrast, initiating antiviral therapy at delivery is unlikely to have an immediate effect on viral replication; therefore, it is not indicated as it does not decrease the risk of neonatal HSV infection.
Vertical HSV transmission risk increases with the duration of membrane rupture; therefore, tocolytic administration is not recommended. Fetal scalp electrodes are avoided in patients with HSV because they cut the fetal skin and create a possible portal for HSV, thereby increasing the risk of vertical transmission.
Vertical transmission of HSV at delivery can cause neonatal meningoencephalitis or sepsis, which often results in long-term sequelae (eg, blindness, neurocognitive disability, persistent seizures).
Neonatal herpes simplex virus infection