What is the course of herpes during pregnancy?
Herpes caused by the herpes simplex virus is not uncommon during pregnancy, as the hormonal changes that accompany it actually promote virus reactivation in many cases. Therefore, herpes suddenly reappears in some women during pregnancy after they have had no outbreaks for years.
The pregnancy-related hormonal changes seem to weaken the immune system slightly, making it easier for the herpes viruses to come out of their “nerve cell hiding place.” A similar phenomenon is observed in some women during menstruation. The risk of initial infection, on the other hand, is no greater during pregnancy than usual.
How is herpes transmitted to the child?
There are three ways in which herpes simplex viruses are transmitted from mother to child:
- During pregnancy via the placenta (transplacental).
- During the birth process (intrapartum) via contact infection
- Shortly after birth (postpartum)
About 85 percent of infections occur at birth, about ten percent occur after birth, and about five percent occur during pregnancy.
During childbirth, there is a possibility that the genital herpes infection will rise through the vagina and infect the child while still in utero. However, this happens only after the rupture of the membranes, when the cervix is already open and the viruses have an easier time penetrating.
If the mother suffers from active genital herpes during childbirth, there is a relatively high risk of transmission to the baby. In this case, the herpes is transmitted directly from the diseased areas in the genital area of the mother to the newborn baby as it passes through the birth canal.
There is also a risk of infection with herpes after birth. Newborns do not yet have a fully developed immune system and are therefore much more susceptible to infection.
What is the course of the different forms of herpes in pregnancy?
In the case of herpes in pregnancy, the region of the body where the disease breaks out is of crucial importance. This is because the risk of transmission to the child depends on it.
For herpes in infants, the form of genital herpes is usually responsible. The typical causative agent of genital herpes is herpes simplex virus 2 (HSV-2). However, it is possible for herpes simplex virus 1 (HSV-1) to cause genital herpes.
Thus, both virus types may trigger herpes in the baby and mother, but HSV-2 is much more often responsible.
Why are first-time herpes infections more dangerous?
It makes a difference whether herpes during pregnancy is a first-time infection or a reactivation of viruses already present in the body. This is because
- a first-time infection with herpes usually lasts longer and more viruses are shed,
- the mother does not yet have antibodies because she has never had contact with the herpes simplex viruses before, and
- antibodies do not prevent repeated outbreaks of herpes (reactivations), but they do mitigate the course compared to the initial infection.
During pregnancy, the mother passes the antibodies against herpes to the child. If it is infected with herpes at birth, they help fight the viruses and cause a weakened course of the disease or even prevent infection.
If, on the other hand, an outbreak of herpes during pregnancy is a first-time infection, the child does not have antibodies and is defenceless against the viruses.
What are the herpes symptoms in newborns?
After infection, it takes several days for symptoms to appear in the child. Sometimes even weeks pass before the first symptoms appear.
The herpes viruses enter the child’s body through the skin, mucous membrane or eyes and initially multiply in superficial skin cells or in the cornea of the eye. In most cases, the infection does not remain confined to a small area, but spreads to the entire surface of the body and the mucous membranes.
Doctors refer to this as a disseminated or generalized herpes infection. Disseminated herpes infection occurs in about a quarter of herpes infections in newborns. Signs include:
- Small herpes blisters typically appearing all over the skin, which burst after some time and leave ulcers on the skin
- On the eyes, there is inflammation and clouding of the cornea. Sometimes the infection spreads to the interior of the eye, possibly leading to blindness.
- Often, general, non-specific signs of illness appear, such as fever, vomiting, refusal to eat and severe exhaustion.
In the worst case, the brain is also affected, resulting in herpes simplex encephalitis. Such an inflammation of the brain, often accompanied by seizures, is extremely dangerous and often ends with the death of the newborn.
Treatment of disseminated herpes in newborns is instrumental in survival, although the disease is sometimes fatal despite therapy. If newborns survive the severe herpes infection, neurologic sequelae remain, leading to developmental delays.
Herpes symptoms in the unborn child
If herpes during pregnancy is transmitted by viruses in the mother’s bloodstream to the unborn child, this usually results in severe complications. For example, malformations occur in the fetus (microcephaly, hydrocephalus, microophthalmia), or the mother suffers a miscarriage.
However, infection of the unborn child with herpes during pregnancy via the blood or placenta is very rare.
What is the risk?
Newborns in whom the herpes is limited to the skin or eyes have the best chances of recovery. In the case of inflammation of the central nervous system or the brain, as well as other organs such as the liver or lungs, the chances of survival are poor. If these organs are spared, early treatment is usually successful. If left untreated, about 50 to 90 percent of herpes-infected newborns die.
Sometimes dangerous reactivations occur in affected children years after a herpes neonatorum. In these, the viruses often attack the retina of the eye and in some cases lead to blindness. Such reactivation may occur even if the initial infection itself was mild and successfully treated at an early stage.
Routine screening for herpes in pregnant women who are asymptomatic is usually not necessary as long as there are no known episodes of genital herpes in the sexual partner. However, in rare cases, the mother may shed virus even though she is asymptomatic. Therefore, even in apparently healthy mothers, herpes in newborns is generally to be expected.
Preventing herpes during pregnancy
In order to avoid the life-threatening herpes infection in the newborn, it is advisable that expectant parents observe a few points.
Herpes reactivation cannot be safely avoided. However, a strong immune system of the pregnant woman reduces the risk of herpes during pregnancy. The immune system can be supported by avoiding additional stress factors. This means getting enough and regular sleep, making sure you eat a healthy diet rich in vitamins, and avoiding physical overload.
How do you treat herpes during pregnancy?
In many cases, doctors prescribe so-called antivirals for herpes. These are antiviral drugs that prevent the herpes viruses from multiplying. However, if a herpes infection occurs during pregnancy, doctors usually make the use of drug treatment dependent on certain factors. An important role is played by the type of herpes infection, whether the pregnant woman has been infected with the virus for the first time and at what point in the pregnancy the infection occurred.
In which case a therapy is necessary for a herpes simplex infection in pregnant women and which drugs are used, you can read in the article: Herpes – Treatment.
