As an expectant parent eagerly
awaiting the birth of your new baby, you are probably taking a number of steps to ensure
your baby's health. One step many experts recommend is that you become informed about
herpes simplex virus (HSV). Infection with this common virus is usually mild in adults;
however, in infants, HSV can cause a rare, but serious, illness.
What is herpes simplex virus?
HSV can cause sores on the face and lips (facial herpes, for example "cold
sores"), or sores on the genitals (genital herpes). HSV-1 is the usual cause of
facial herpes, and HSV-2 is the usual cause of genital herpes. But either type of HSV can
infect either part of the body. Either type can also infect a newborn baby.
How common is herpes simplex virus?
Figures for those infected with HSV-2 vary widely across different countries and between
different populations. The prevalence of HSV-2 infection varies worldwide. Around 25% of
American adults compared with around 4-14% of Europeans and Australians are infected with the virus. The
proportion of genital herpes due to HSV-1 infection is high or increasing in many
countries (e.g. England, Scotland, USA, Denmark, the Netherlands and Japan).
You can get genital herpes if you have sexual contact
with a partner who is infected with HSV, or if a partner with HSV infection performs oral
sex with you. Most people with HSV don't know they are infected because they have no
symptoms, or their symptoms are too mild to notice.
How can herpes simplex spread to an infant?
- HSV is most often spread to an infant during birth if the
virus is present in the birth canal during delivery.
- HSV can also be spread to the baby if he or she is kissed
by someone who suffers from coldsores.
- In rare instances, HSV may be spread by touch, if someone
touches an active cold sore and immediately touches the baby.
How can herpes harm a baby?
HSV can cause neonatal herpes, a rare but life-threatening disease. Neonatal herpes can
cause skin, eye or mouth infections, damage to the central nervous system and other
internal organs, mental retardation, or death. Medication may help prevent or reduce
lasting damage if it is given early.
How many babies get neonatal herpes?
Although genital herpes is common, the risk of your baby being affected by neonatal herpes
is low particularly if you contracted genital herpes before the third trimester of
pregnancy. In the USA one in 1800-5000 live births are affected, in the UK one in 60 000,
in Australia and France one in 10 000 and in the Netherlands one in 35 000 are affected.
This means that the majority of women with genital herpes give birth to healthy babies.
Which babies are most at risk?
Babies are most at risk from neonatal herpes if the mother contracts genital HSV infection
in the final trimester of pregnancy. This is because a newly infected mother has not yet
produced sufficient antibodies against the virus, so there is virtually no natural
protection for the baby before and during birth. In addition, newly acquired genital HSV
infection is frequently active, so it is probable that the virus will be present in the
birth canal during delivery.
What about pregnant women who have a history of
genital herpes?
Women who acquire genital herpes before they become pregnant have a very low risk of
transmitting HSV to their babies. This is because their immune system has already produced
antibodies that are passed to the baby in the bloodstream through the placenta. Even if
HSV is active in the birth canal during delivery, the antibodies help to protect the baby.
In addition, if a mother knows she has genital herpes, her doctor can take steps to
protect the baby.
Protecting the baby: women with genital herpes
If you are pregnant and you have genital herpes, you may be concerned about the risk of
spreading the infection to your baby. Be reassured that the risk is extremely small
especially if you have had herpes for some time. The following steps can help make the
risk even smaller:
- Talk with your family doctor, obstetrician or midwife.
Make sure he or she knows you have genital herpes.
- At the time of labour, check yourself for any symptoms in
the genital area - sores, itching, tingling or tenderness. Your doctor will also examine
you with a strong light to detect any signs of an outbreak.
- Your obstetrician should ideally discuss the choices for
managing an active herpes outbreak at the time of delivery with you early in the
pregnancy. The choices are to proceed with a vaginal delivery (avoiding routine use of
instruments) or to have a Caesarean section. There is currently insufficient information
to clearly support one option or the other; the risk of transmission with vaginal delivery
is very low and must be weighed against the risk of Caesarean section to the mother.
- Ask your doctor not to break the bag of waters around the
baby unless necessary. The bag of waters may help protect the baby for as long as possible
against any virus in the birth canal.
- Ask your doctor not to use a foetal scalp monitor (scalp
electrodes) during labour to monitor the baby's heart rate unless medically necessary.
This instrument makes tiny punctures in the baby's scalp, which may allow HSV to enter. In
most cases, an external monitor can be used instead.
- Ask that a vacuum or forceps are not used during delivery
unless medically necessary. These instruments can also cause breaks in the baby's scalp,
which may allow HSV to enter.
- After birth, watch the baby closely for about 4 weeks.
Symptoms of neonatal herpes include blisters on the skin, fever, tiredness, irritability,
or lack of appetite. While these symptoms can be initially mild, don't wait to see if your
baby will get better. Take him or her to a physician at once. Be sure to tell the
physician you have genital herpes.
- Think positively! The odds are strongly in favour of you
having a healthy baby.
Protecting the baby: women who don't have
genital herpes
The greatest risk of neonatal herpes is to babies whose mothers contract genital infection
in the final trimester of pregnancy.
While this is a rare occurrence, it does happen, and can
cause a serious, even life-threatening, illness for the baby. The best way you can protect
your baby is to know the facts about HSV and how to protect yourself. The first step may
be finding out whether you already carry the virus. If you have a partner who knows they
have genital herpes and you don't know whether you have it, you need to discuss this with
your doctor.
How can I get tested for genital HSV?
If you have genital symptoms, the most usual test is a virus culture which detects HSV
from the affected genital site(s). To perform this test, your doctor must take a sample
from the site of a herpes outbreak while it is active, preferably on the first day. Test
results are available in around 7 days.
If you don't have symptoms, a blood test can tell
whether you are infected with HSV-2, the type of HSV that usually infects the genital
tract. (A blood test may also tell you whether you have HSV-1, but in many cases this
simply means you have facial herpes).
The most accurate blood test is the Western blot, but
this is largely a research tool. Other tests, such as immunoblot assays and POCKitTM
tests are more widely available. Some of these tests can only identify HSV-2 infection,
others may detect HSV-1 and HSV-2, or not specify.
Ask your doctor about these tests as availability
differs between countries and some tests are not as accurate as others.
How can I make sure I don't get genital HSV
infection?
If you test negative for genital herpes, the following steps can help protect you from
acquiring the infection during pregnancy:
- If your partner has genital herpes, abstain from sex
during active outbreaks. Between outbreaks, he should use a condom from start to finish
every time you have sexual contact, even if your partner has no symptoms (HSV can spread
when no symptoms are present). Get your partner to talk with your doctor about using
suppressive oral antiviral therapy for the duration of the pregnancy. Consider abstaining
from sex during the last trimester.
- If you don't know whether your partner has genital
herpes, you may wish to ask him to be tested. If your partner has genital or facial HSV
infection, there is a chance that you may acquire it unless you take steps to prevent
transmission.
- Do not let your partner perform oral sex with you if he
has an active cold sore (facial herpes). This can give you genital herpes.
What if I contract genital HSV during late
pregnancy?
If you experience genital symptoms, or believe you have been exposed to genital HSV, tell
your obstetrician or midwife at once as infection during this time presents the greatest
risk of transmission to your baby. However, be aware that herpes can lie dormant for
several years. What appears to be a new infection may be an old one that is causing
symptoms for the first time. Blood tests can tell whether your symptoms are the result of
an old infection or if you have recently acquired genital HSV infection.
Talk with your doctor about the best way to protect your
baby. When a pregnant women does contract genital HSV infection during the last trimester,
some doctors will prescribe an antiviral medication. Some recommend a Caesarean delivery
under these circumstances, even if no outbreak is present.
How can I protect the baby after birth?
A baby can get neonatal herpes in the first few weeks after birth. Such infections are
almost always caused by a kiss from an adult who has a cold sore. To protect your baby, do
not kiss him or her when you have a cold sore, and ask others not to. If you have a cold
sore, wash your hands before touching the baby.
For partners of pregnant women
If your partner is pregnant, and she does not have genital HSV infection, you can help
ensure that the baby remains safe from the infection. Find out whether you have genital
HSV (see "How can I get tested?"). Remember, approximately 20% of sexually
active adults do have genital HSV infection, and most do not have symptoms. If you find
that you have the virus, follow these guidelines to protect your partner during the
pregnancy:
The best way to protect the baby
from neonatal herpes is to prevent genital HSV during late pregnancy.