Correct Answer: A. Acyclovir and elective Cesarean section
Primary genital herpes simplex virus (HSV) infection at term with active vesicular lesions mandates elective Cesarean section to prevent neonatal herpes transmission during vaginal delivery. The discriminating fact is that active herpetic lesions at delivery carry a 30–50% risk of neonatal transmission, causing potentially fatal disseminated disease, encephalitis, or blindness in the newborn. Acyclovir is given to the mother to reduce viral shedding and shorten lesion healing, but it does NOT eliminate the risk sufficiently to permit vaginal delivery. Indian guidelines (FOGSI, ICOG) and Harrison recommend Cesarean delivery when active lesions are present at term or when labor begins with active disease. The timing is "elective" (planned before labor onset) because rupture of membranes or labor with active lesions increases fetal exposure. Acyclovir therapy (800 mg 5 times daily from 36 weeks or at diagnosis) reduces recurrence risk and viral load but is adjunctive, not a substitute for surgical delivery. The absence of rashes elsewhere confirms localized genital HSV, not disseminated varicella-zoster, which would have different management implications.
Why the other options are wrong
B. Antiviral and normal vaginal — This is wrong because antiviral therapy alone does NOT reduce neonatal transmission risk to safe levels when active lesions are present. Vaginal delivery with active herpetic lesions carries 30–50% risk of neonatal herpes, which is unacceptable. NBE traps students who believe antivirals are sufficient; they reduce maternal symptoms and viral load but do not eliminate fetal exposure during passage through an infected birth canal. Vaginal delivery is only considered if lesions have completely healed and crusted over (typically 7–10 days post-onset). C. Acyclovir and induction of labor — This is wrong because induction of labor with active herpetic lesions increases the risk of prolonged rupture of membranes and ascending infection, worsening neonatal exposure. Acyclovir does not make vaginal delivery safe when lesions are present. The goal is to avoid labor and vaginal delivery entirely when active disease exists at term. Induction is contraindicated because it forces passage through an infected birth canal. This option represents a dangerous compromise that combines correct drug therapy with incorrect delivery route. D. Spontaneous delivery — This is wrong because spontaneous vaginal delivery with active herpetic lesions exposes the fetus to direct contact with infectious viral particles, resulting in 30–50% neonatal transmission. Spontaneous labor may also lead to prolonged rupture of membranes, increasing ascending infection risk. NBE may include this to test whether students understand that expectant management is inappropriate when active lesions are present at term. Spontaneous delivery is only acceptable if lesions have completely resolved and re-epithelialized.
High-Yield Facts
- Primary HSV at term with active lesions → elective Cesarean section is mandatory; vaginal delivery carries 30–50% neonatal transmission risk.
- Acyclovir dosing in pregnancy: 800 mg orally 5 times daily from 36 weeks gestation or at diagnosis of primary/first-episode HSV; reduces recurrence and viral shedding but does NOT replace Cesarean delivery.
- Neonatal herpes consequences: disseminated disease, CNS encephalitis, keratoconjunctivitis, and death in 30% of untreated cases; Cesarean delivery reduces risk to <5%.
- Recurrent HSV at term: vaginal delivery is acceptable if lesions have completely healed and crusted (typically 7–10 days post-onset); risk of transmission is <1% in recurrent disease.
- Timing of Cesarean: elective (planned before labor onset) to avoid rupture of membranes and ascending infection; if labor begins with active lesions, emergency Cesarean is indicated.
Mnemonics
HSV at Term: CAVE Cesarean section (elective), Acyclovir (800 mg 5×/day), Vesicular lesions (active = contraindication to vaginal delivery), Encephalitis risk (neonatal). Use this when you see 'active herpetic lesions at term' to lock in Cesarean + acyclovir. Neonatal Herpes Risk Memory Hook '30–50% with vaginal, <5% with Cesarean' — the numbers alone justify surgical delivery. Repeat this when deciding delivery route in active HSV.
NBE Trap
NBE pairs "antiviral therapy" with "vaginal delivery" to trap students who believe antivirals are sufficient to prevent neonatal transmission. The trap is that acyclovir reduces maternal symptoms and viral load but does NOT eliminate fetal exposure during passage through an infected birth canal; only Cesarean delivery achieves this.
Clinical Pearl
In Indian tertiary centers, neonatal herpes is rare but catastrophic when it occurs; a single case of disseminated neonatal HSV with encephalitis or blindness justifies the morbidity of elective Cesarean section. Primigravidas with primary HSV at term are at highest risk because they lack maternal antibodies to transfer to the fetus, making Cesarean delivery non-negotiable.
_Reference: Harrison Ch. 187 (Herpes Simplex Virus Infections); FOGSI Obstetric Practice Guidelines on Sexually Transmitted Infections in Pregnancy; DC Dutta's Textbook of Obstetrics Ch. 23 (Infections in Pregnancy)_