Herpes and having babies
Herpes and pregnancy: what you need to know
Herpes simplex virus (HSV) commonly causes oral (HSV-1) or genital (HSV-2) infections. When you’re pregnant or planning a pregnancy, understanding how herpes can affect you and your baby is important for reducing risks and making informed decisions.
Risk of neonatal herpes: The greatest concern is neonatal herpes, a rare but potentially severe infection in the newborn. It most commonly occurs when a baby is exposed to HSV in the birth canal during a vaginal delivery, especially if the mother acquires a new genital HSV infection late in pregnancy (third trimester). Primary infections near delivery carry the highest risk because the mother hasn’t yet developed protective antibodies to pass to the baby.
Timing matters:
Primary (first) genital HSV infection in late pregnancy: highest risk of transmission to the newborn.
Recurrent genital HSV during delivery: much lower risk because maternal antibodies reduce transmission likelihood.
Oral HSV (cold sores) can also pose a risk if active lesions near the mouth come into contact with the newborn, although transmission pathways differ.
Potential outcomes for the baby if infected
Localized disease: Skin, eye, or mouth infections are possible and can often be treated successfully if detected early.
Central nervous system disease: HSV can cause encephalitis or other neurologic problems, which may lead to long-term disabilities.
Disseminated disease: Widespread infection affecting multiple organs; this can be life-threatening without prompt antiviral treatment.
Early diagnosis and treatment improve outcomes substantially.
Diagnosis and screening
Routine prenatal screening for HSV in people without symptoms is not generally recommended because many people are asymptomatic carriers and tests can be misleading. Instead, testing is often based on history or symptoms.
If a pregnant person has symptoms (painful sores, blisters), they should inform their provider immediately. A swab of a suspected lesion can confirm active infection.
Serologic (blood) testing can identify past exposure (HSV antibodies). This information can help assess risk, particularly if a partner has genital herpes or there’s concern about a new exposure during pregnancy.
Prevention and management strategies
Antiviral therapy: For people with a history of genital herpes, many providers recommend antiviral prophylaxis (typically oral acyclovir or valacyclovir) starting around 36 weeks’ gestation to reduce the chance of an outbreak at delivery.
Delivery planning:
If active genital lesions or prodromal symptoms are present at the onset of labor, cesarean delivery is usually recommended to reduce neonatal exposure.
If there are no lesions and no prodromal symptoms near delivery, vaginal birth is often considered safe, especially for those with recurrent HSV.
Treating suspected neonatal infection: Newborns suspected of having HSV are evaluated and treated promptly with intravenous antivirals. Early treatment is critical for the best outcomes.
Preventing maternal acquisition late in pregnancy:
Avoid sexual contact with partners known to have active genital herpes during the third trimester.
Use barrier protection and consider partner testing or suppressive therapy for partners if appropriate.
Counseling and emotional support
Disclosure and communication: Discussing HSV status with partners and your prenatal care team helps create a clear management plan.
Emotional impact: Learning you have HSV during pregnancy can be stressful. Ask your provider for education, counseling resources, and support groups.
Family planning: Many people with HSV have healthy pregnancies and children. With proper medical management and precautions, risk to the baby is low.
Key takeaways
The highest risk to a newborn is when the mother acquires genital herpes late in pregnancy.
Antiviral prophylaxis late in pregnancy and cesarean delivery if lesions are present at labor significantly reduce neonatal risk.
Prompt evaluation and treatment of suspected neonatal HSV improves outcomes.
Talk openly with your healthcare provider about history, testing, and delivery planning to protect you and your baby.
