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Getting herpes in late pregnancy

Women who become infected with herpes during their last trimester and/or experience their first episode of genital herpes late in pregnancy are the most at risk of experiencing complications.

This is because few, if any, antibodies have time to be passed on to your baby before birth. The biggest risk of herpes transmission to an infant occurs when a mother experiences a herpes outbreak at the time of delivery.

As the child passes through the birth canal, the newborn is exposed to the herpes sores. About half of all newborns born vaginally to a mother with a herpes outbreak will be infected with the HSV virus.

Other factors that can increase a fetus' risk of herpes infection include being born prematurely (as these babies will not receive a "full dose" of antibodies at the time of their birth) and using medical instruments during a vaginal birth (which may puncture the child's skin, making it easier for the virus to enter the body).

Although it is rare, it is also possible for the herpes virus to be passed through the placenta to the fetus. This is known as congenital herpes.

Herpes Treatment

Because the typical herpes treatments are not necessarily suitable for pregnant women, typical genital herpes treatment in pregnancy involves extra monitoring by your health care professional.

So long as you do not have a herpes outbreak at the time of delivery, it is generally thought to be safe to have a vaginal birth.

Herpes medication that can help suppress the symptoms and frequency of herpes outbreaks are generally not suitable for use during pregnancy.

Some pregnant women, though, may be prescribed acyclovir during their third trimester to help suppress an outbreak. However, this drug has not been approved by the FDA as safe to use during pregnancy and is classified as a type B drug.

This means that is only recommended for use when the benefits of the drug outweigh the risks. The long-term effects of this drug on the child have not been properly evaluated and more study is needed.

Of the few tests that have been done, though, all have shown the drug to cause no ill side effects in the child or mother.

If you have a herpes outbreak at the time of birth, a cesarean section will be done to minimize the risk of transmission. If your outbreak occurs shortly before you expect to deliver, your health care provider will closely monitor you and evaluate how infectious you are.

So long as you do not have any herpes lesions or viral shedding, a vaginal birth is generally thought to be okay.