Herpes simplex virus (HSV) is a widespread viral infection that can cause painful blisters or ulcers. While manageable in adults, its presence during pregnancy requires specific consideration for newborn health.
How Herpes Can Be Passed to a Baby
Herpes simplex virus can be transmitted from a parent to an infant. The most common route, accounting for about 85% of cases, occurs when the baby passes through the birth canal during vaginal delivery. This risk is higher if the birthing parent has active genital lesions or is shedding the virus. Many individuals may not be aware they have HSV sores or are shedding the virus asymptomatically.
Transmission during pregnancy, while rare (about 5% of cases), can occur if the virus crosses the placenta. This intrauterine transmission is most likely if a pregnant person acquires a primary herpes infection late in pregnancy, before developing protective antibodies.
After birth, postnatal transmission makes up about 10% of neonatal cases. This typically happens through direct contact with an infected person, such as from a cold sore or skin lesion. Both Herpes Simplex Virus type 1 (HSV-1), associated with oral herpes, and Herpes Simplex Virus type 2 (HSV-2), which causes genital herpes, can be transmitted. While HSV-2 has historically been more common, HSV-1 is increasingly responsible for neonatal infections in some regions.
Preventing Transmission to Your Baby
To prevent herpes transmission to your baby, inform your obstetrician or midwife about any history of genital herpes or potential exposure. If your partner has genital herpes, consider using condoms throughout pregnancy, especially in the last trimester, or your partner may consider suppressive therapy to reduce transmission risk.
Antiviral medication is a primary defense against herpes transmission during late pregnancy. Doctors may prescribe antiviral drugs like acyclovir or valacyclovir, typically starting around 36 weeks of gestation and continuing until childbirth. This suppressive therapy can reduce the frequency and severity of outbreaks, minimizing the chance of active lesions at delivery. Studies suggest this approach can also lower the need for a cesarean section (C-section) due to herpes.
If active genital lesions are present, or if there are symptoms suggesting an impending outbreak at the time of labor, a C-section is often recommended. This surgical delivery bypasses the birth canal, reducing the baby’s exposure to the virus. Even with a C-section, the risk is reduced but not entirely eliminated. Communicate any symptoms, even subtle ones like itching or tingling, to your medical team to ensure the safest delivery plan.
Recognizing Neonatal Herpes and Its Impact
Neonatal herpes is a herpes simplex virus infection that develops in a baby, typically within the first six weeks of life. This condition is serious for newborns because their developing immune systems make them vulnerable to widespread infection. Without prompt treatment, neonatal herpes can lead to severe complications, including neurological damage, intellectual disability, or even death.
Symptoms often appear between one and three weeks after birth, though they can emerge up to four weeks later. Common signs include skin lesions, which may present as small, fluid-filled blisters that can break and crust over. However, some babies with more severe forms affecting internal organs or the central nervous system may not exhibit skin lesions. Other symptoms can be non-specific, such as lethargy, poor feeding, irritability, high-pitched crying, fever, or seizures.
Diagnosis involves various tests, including viral cultures, polymerase chain reaction (PCR) testing of blood or cerebrospinal fluid, or samples from lesions. Early diagnosis is important for improving outcomes, as immediate treatment is necessary to prevent the infection from progressing. Treatment typically involves high-dose intravenous antiviral medication, such as acyclovir, administered for several weeks.
Considerations After Birth
After your baby is born, ongoing precautions are necessary to prevent postnatal herpes transmission, especially if you or another caregiver have active herpes lesions. Always wash your hands thoroughly with soap and water before touching your baby, especially after touching any active sores. It is also advised to avoid kissing the baby on the mouth if you have a cold sore or any active oral herpes lesions.
Breastfeeding is generally considered safe for parents with herpes, as the virus is not transmitted through breast milk. However, specific precautions are needed if active lesions are present on the breast or nipple. If there are sores on a breast, temporarily stop breastfeeding from that affected breast and discard any expressed milk from that side until the lesions have completely healed. Breastfeeding can continue from the unaffected breast, provided the active lesions on the affected breast are fully covered to prevent direct contact with the baby.