Genital herpes during pregnancy is usually safe to carry, and most people with the virus deliver healthy babies. The real danger is a first herpes infection caught late in pregnancy, which can pass to the newborn at birth and cause severe illness. Long-standing recurrent herpes carries a much lower risk, and daily antivirals plus careful delivery planning lower it further.
about 12%
but well controlled
| Item | Value |
|---|---|
| Adults 14–49 with HSV-2 | ~1 in 8 — about 12% |
| Unaware they have it | ~87% |
| Daily antivirals cut spread | ~50% |
| Cure | none — but well controlled |
Why genital herpes matters when you're pregnant
Genital herpes is caused by two related viruses, herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) CDC. Both set up a lifelong infection. There's no cure. Antivirals control symptoms without clearing the virus from the body. For most adults that's a manageable nuisance. In pregnancy the stakes shift, because the same virus that causes mild or invisible symptoms in you can be dangerous to a newborn whose immune system isn't ready to fight it.
Most genital herpes spreads from someone who has no idea they're infected. Most people with HSV-2 have no symptoms or symptoms so mild they're missed, and the majority of HSV-2 infections are never diagnosed. People with HSV-2 shed virus on about 10% of days even when they never get an outbreak, and most of that shedding leaves no visible sore JAMA. A partner can pass it during pregnancy without either of you knowing, so the absence of sores is no guarantee of safety.
If you're not sure of the difference between the bumps and lesions of herpes and other conditions, our guides on genital herpes symptoms and hpv vs herpes walk through what each actually looks and feels like.
What are the risks to the baby?
The serious outcome is neonatal herpes, a herpes infection in the newborn that can attack the skin, eyes, mouth, brain, and other organs, and is potentially deadly. A baby almost always catches it during vaginal delivery, by passing through a birth canal where the virus is present. Infection earlier in pregnancy is rare but can contribute to miscarriage or preterm (early) delivery.
The single biggest factor is whether your herpes is brand new or long-standing:
- A first-time outbreak near the time of delivery carries the highest risk. You haven't yet made protective antibodies to pass to the baby, the virus tends to be shedding heavily, and the newborn meets a large viral load with no inherited defense.
- A recurrent outbreak in someone who's had herpes for a while carries a much lower risk. By then your body has built antibodies that cross the placenta and partly protect the baby, recurrent outbreaks shed less virus, and they heal faster.
This is why your clinician will ask carefully whether a sore in late pregnancy is your first ever or one of many. The answer changes the plan.
Should you be screened for herpes in pregnancy?
For people without symptoms, the answer is generally no. The U.S. Preventive Services Task Force recommends against routine blood (serologic) screening for genital herpes in asymptomatic adolescents and adults, including pregnant people, a Grade D recommendation USPSTF, 2023. The benefit is no greater than small, while the harms are at least moderate. Herpes blood tests produce a lot of false positives, and a wrong-positive result during pregnancy can cause real anxiety and relationship strain without protecting the baby.
Testing still has a place when there's a reason for it. If you develop sores, a clinician can swab an active lesion for the most reliable diagnosis. If a partner has herpes, that's worth discussing directly with your prenatal provider so they can plan. For timing of any STI testing after a possible exposure, see when to test after exposure, and you can get tested if you have symptoms or a known exposure during pregnancy.
Is herpes treatment safe during pregnancy?
Yes, the standard antivirals are used routinely in pregnancy. Three FDA-approved drugs treat herpes: acyclovir, valacyclovir, and famciclovir CDC STI Tx Guidelines. They control outbreaks and reduce shedding but don't cure the infection or change how often it comes back once you stop. In late pregnancy, clinicians commonly prescribe daily suppressive antiviral therapy, a pill taken every day rather than only during an outbreak, to lower the chance of an active outbreak or viral shedding at delivery.
Two ways to take antivirals are worth understanding:
| Approach | How it's taken | What it's for in pregnancy |
|---|---|---|
| Episodic therapy | A short course started at the first sign of an outbreak | Shortens and eases an individual outbreak |
| Suppressive therapy | One pill daily, often started in the last weeks before delivery | Reduces outbreaks and shedding around the time of birth, lowering the chance a C-section is needed |
In people who get frequent recurrences, suppressive therapy cuts outbreaks by 70%–80%. It also lowers transmission to a partner: in a randomized trial of couples where one partner had HSV-2, daily valacyclovir reduced the risk of passing the virus by about 48% Corey et al., useful if your partner is pregnant and you're the one with herpes. Cost and access are rarely a problem, since acyclovir and valacyclovir are inexpensive generics, and a clinic visit during an outbreak gives the most reliable diagnosis and prescription. For day-to-day management between visits, our guide to herpes outbreak triggers & how to prevent them covers what tends to set outbreaks off.
Reducing the chance of passing herpes at delivery
The plan hinges on whether you have signs of an active outbreak when labor starts:
- No sores and no prodrome at labor: a vaginal delivery is usually fine, especially for long-standing recurrent herpes.
- Active sores or warning prodrome (tingling, itching, or pain that signals an outbreak coming) at labor: a cesarean delivery is generally recommended to keep the baby from contacting the virus in the birth canal.
- Daily suppressive antivirals in the final weeks reduce the odds of an outbreak or shedding at delivery, so they're offered to many pregnant people with a herpes history.
Protecting yourself from acquiring herpes in the third trimester matters just as much, since a new infection late in pregnancy is the high-risk scenario. If a partner has herpes (or HSV-1, the oral-type virus that can be passed to the genitals through oral sex), consider avoiding genital and oral-genital contact in the last trimester, or having that partner take daily suppressive therapy. The most common mistake is assuming no visible sore means no risk. Herpes spreads silently, so open disclosure between partners does more to prevent a late-pregnancy infection than watching for blisters.
When to see a clinician
Tell your prenatal provider early if you or your partner has ever had genital herpes, even if outbreaks are rare. Reach out promptly if you notice genital sores, blisters, or the tingling and burning of a prodrome, particularly in the third trimester. Seek care right away for a possible first-ever outbreak in late pregnancy, since that situation needs the most planning. After birth, watch the newborn and call the pediatrician for fever, poor feeding, listlessness, a rash or blisters, or seizures, and mention any herpes history so the baby is evaluated quickly.