Herpes is a very common viral infection in adults that can pose a great risk to your developing baby and newborn. Herpes is caused by the Herpes Simplex Virus 1 & 2 (HSV 1 & 2).
Symptoms include painful blisters near the mouth and/or genitals. When the blisters heal, the virus remains dormant deep in a sensory nerve only to often reactivate at a later time. If you have been exposed to the virus, it will always remain in your body and you are a carrier. There is currently no cure. A problem with herpes infections is that most women (90%) who have the virus have never had any noticeable symptoms or skin lesions. They are therefore unaware that they carry it.
HSV 1, often associated with oral herpes, is the more common form of the virus and is present in nearly half of all women. HSV 2, mostly associated with genital herpes, is present in about 25% of all women. Both HSV 1 and HSV 2 can, however, cause either oral or genital infections. Due to the prevalence of oral sex, close to half of all new genital infections are now due to HSV 1.
Primary and secondary infection
The first time a person is exposed to the virus, the resulting infection is known as a primary infection. The incubation time is between 2 and 12 days before the blisters appear. This primary infection is associated with a much higher concentration of virus and the symptoms, if present, are usually more significant than with reactivation of the virus from its dormant stage, known as a secondary infection. If the primary infection is genital, symptoms often include painful genital ulcers, painful enlarged lymph nodes in the groin, and pain with urination. Headache and fever are also often seen.
A secondary infection is less symptomatic and is often not associated with any symptoms at all. Viral shedding from a carrier is also very common and is usually asymptomatic. It lasts on average 2 weeks but can last for many months. Viral shedding is infectious and occurs much more commonly after a primary infection than a secondary one. Due to this prolonged shedding, primary infections in pregnancy should be treated very aggressively with antiviral medications.
Herpes infection of the newborn, also called neonatal herpes, is a very severe illness. It is rare for the virus to reach and infect your baby during the pregnancy prior to labor, although it can happen in rare cases with a primary infection.
If you have an outbreak or symptoms of a genital outbreak during labor, the virus will usually be present in the vaginal fluids and your baby can get infected as it comes down your birth canal. Primary infections are the most worrisome due to the high concentration of virus present in the birth canal. The risk of a neonatal infection in these cases is about 30% or more.
If you have a secondary infection during labor, the concentration of the virus in the vaginal secretions is significantly lower. In addition to the lower viral concentration, there are neutralizing antibodies present (these start forming 3 weeks after a primary infection) in you that will travel to your baby via the placenta and provide an additional degree of protection for your baby. The neonatal infection rate with a mother’s secondary infection is, therefore, much lower than with a primary infection (about 3%).
In both cases, however, the risk is high enough, that a cesarean birth will be recommended to you to lower the risk of transmission to your baby. If you have a history of herpes, an examination will routinely be performed on you when you are in labor. If there are lesions present or if you have symptoms indicative that you might be getting an outbreak, a cesarean will most likely be recommended. Do note that if your lesions are crusted over, they are not considered active. Finally, active non-genital HSV legions are not felt to transmit the virus to your baby and a vaginal birth is felt to be safe as long as these lesions are covered up well.
A precaution that your obstetrician or midwife might follow, if you have a history of herpes but no outbreak, is to avoid a fetal scalp electrode unless medically necessary. Scalp electrodes can cause a small break in the fetal skin and this could increase the risk of your baby getting infected if you are shedding the virus and unaware of it.
How can you reduce the risk of getting an outbreak near the time of labor?
Since the most important time to prevent reactivation and viral shedding is at the end of the pregnancy, many health care providers suggest suppression with antiviral medications starting at 36 weeks. Studies have shown that if you have a history of recurring outbreaks, there is an up to 75% chance that you will get an outbreak during your pregnancy and a 15% chance you will get an outbreak around the time you are in labor.
The suppression can either be oral Acyclovir 400 mg 3 times per day or oral Valacyclovir 500 mg orally 2 times per day. The pills should be taken until delivery. They are both deemed safe for pregnancy. Some physicians also offer the same prophylaxis to women with herpes who dont have a history of recurrence, and to women who have never had herpes but whose spouse has it.
A common problem is what to do when you have never had herpes but your spouse has. In a situation like this, there is up to a 20% chance that you will acquire it during your pregnancy. There is no agreement among medical experts about what you should do to reduce the risk. One suggestion is that both you and your spouse do a blood test to verify your infectious status.
If your spouse truly has it and you dont, you might consider taking certain steps to help prevent a primary infection while you are pregnant. This is especially important near the time of labor. Using condoms reduces the risk of transmission by about 50% (see sex in pregnancy).
In addition, having your spouse take prophylactic antiviral medications also seems to reduce the chance of your getting infected by about 50%. Using both of these precautions at the same time will result in a close to 75% reduction in risk for you. Finally, it is generally recommended by most physicians that you abstain from sexually activity, both genital and oro-genital, during the last trimester in a case like this. Do talk to your health care provider about what he or she suggests you do during your pregnancy.
How to minimize the risk for the baby?
If you have herpes, you might wonder how to minimize the risk of infection for your baby after the birth. About 5 to 10% of babies who get neonatal herpes will get it after birth. This often occurs when a parent or other adult with active oral herpes (cold sores) kisses or nuzzles them. Therefore, if you have an outbreak anywhere on your body, cover it well to prevent contact with your baby’s skin and thoroughly clean the surrounding area.
If you have a cold sore, do cover it or use a surgical mask until it has disappeared completely. Remember that herpes can be spread from hand to mouth, so wash your hands frequently and carefully. Kindly ask family and visitors with cold sores to not touch your baby until their outbreaks are over.
If you have a history of oral herpes, don’t trim your baby’s nails with your teeth, even when you dont have a cold sore, since you might be shedding the virus from your lips or mouth. It is safe for you to take antiviral medications while nursing in order to speed up the disappearance of cold sores. Lastly, if you get herpetic cold sores frequently, you can ask your health care provider about being prescribed antiviral medications to suppress outbreaks.
When it comes to nursing your baby while having an outbreak, it is deemed safe as long as you have no lesions on your breasts. Do cover any other lesions you have and wash your hands frequently. If you have an outbreak on one of the breasts, it is thought safe to nurse on the other breast as long as you first cover the lesions on the breast with the outbreak.