Herpes during pregnancy: what should an expectant mother know to take care of herself and her baby?
Herpes during pregnancy is a common topic of medical consultations and a cause for concern. Although in many cases, cold sores on the lips during pregnancy (also known as cold sores) are not a cause for concern, it's always worth knowing when observation, home remedies, and popular ointments from the pharmacy are sufficient, and when symptoms require urgent medical consultation. In this article, we explain whether herpes is dangerous during pregnancy, the difference between labial and genital infections, the importance of herpes during pregnancy in the first, second, and third trimesters, and what can be used to treat herpes during pregnancy without fear of harming the fetus.
Herpes during pregnancy: what is the HSV virus and how can you become infected?
The herpes simplex virus, medically known as HSV ( Herpes Simplex Virus ) , is a DNA virus and one of the most common viruses in humans . For many expectant mothers, the topic of herpes during pregnancy can be a source of concern, but it's worth emphasizing that a significant number of adults have been exposed to HSV before becoming pregnant, often without even realizing it.
There are two main types of herpes simplex virus:
- HSV-1
Herpes simplex virus type 1 is most often responsible for lesions around the mouth and face . It's this virus that's often associated with cold sores during pregnancy , commonly known as cold sores . However, it's worth noting that HSV-1 can also cause lesions in the genital area, especially after oral-genital contact.
- HSV-2
Herpes simplex virus type 2 is more often associated with genital herpes . It is transmitted primarily during intimate contact and may be responsible for recurrent lesions in the vulva, vagina, perineum, or anus. From the perspective of caring for a pregnant woman, the location of the skin lesions is particularly important, as is whether the infection is new or a recurrence of a previous infection.
Expert advises
A characteristic feature of both types of HSV is its ability to remain latent in the body. This means that after initial infection, the herpes virus can survive in the nerve ganglia and remain asymptomatic for a long time. In certain situations, such as weakened immunity, infection, severe stress, fatigue, or hormonal changes, it can reactivate and resurge with vesicles, for example, in the form of cold sores on the lips during pregnancy.
Is herpes dangerous during pregnancy? It depends on the location of the lesions and when the infection occurred.
Herpes during pregnancy may pose a certain risk to the fetus and newborn, but the severity of this risk depends primarily on whether it is the first infection in a woman's life , i.e., a primary infection, or a recurrence of a virus already present in the body. Another crucial distinction is the location of the herpes during pregnancy , as oral herpes is assessed differently than genital herpes during pregnancy , especially if symptoms appear in the third trimester.
Although neonatal HSV infections are rare, they can be severe, so any concerns about herpes during pregnancy should be discussed with your doctor.
Are cold sores dangerous during pregnancy? Key factors in assessing the risk.
A first-time infection with the herpes labialis virus (HSV-1) during pregnancy, although usually much less dangerous than genital herpes, requires vigilance and consultation with a doctor. In 90% of cases, the primary infection (the first infection in life) appears in early childhood. It often has a slightly more severe and systemic course : high fever, headaches, and muscle pain may occur, and lesions on the lips and oral mucosa can be extensive and painful.
Expert advises
In the case of primary infection, the mother experiences viremia, or the temporary presence of the virus in the blood. This, in very rare cases (approximately 5% of all neonatal infections), can lead to intrauterine infection. This situation is most serious in the first 20 weeks of pregnancy and may be associated with the risk of miscarriage or congenital defects.
If you experience cold sores during pregnancy for the first time , don't panic, but consult your doctor as soon as possible . A specialist will select an appropriate and safe herpes treatment that will help prevent systemic complications in the pregnant woman.
Recurrent cold sores in the 1st, 2nd and 3rd trimesters of pregnancy and the risk to the fetus
Recurrent (i.e. not the first time) cold sores on the lips during pregnancy usually do not pose a threat to the unborn child , because the HSV-1 virus in this form does not live in the blood and cannot cross the placenta to the fetus.
Recurrent herpes infection during pregnancy carries a very low risk to the fetus (less than 1–3%) because the mother's IgG antibodies cross the placenta and protect the baby from infection.
Genital herpes during pregnancy in the 1st trimester, 2nd trimester and 3rd trimester
Genital herpes during pregnancy is a major cause for medical concern. If a woman first contracts genital herpes during the first or second trimester, the risk of intrauterine transmission is only about 1% . Although rare, infection during this period can lead to, among other things, spontaneous abortion, fetal growth restriction (IUGR), or severe birth defects such as microcephaly, visual defects, or skin scarring.
Genital herpes is most dangerous in the 3rd trimester of pregnancy
Expert advises
Primary genital infection is most dangerous, especially when HSV-2 infection occurs in the third trimester of pregnancy. The risk of transmitting the virus to the fetus during vaginal delivery ranges from 30% to as much as 50%, as the mother's body does not have time to produce and transmit protective antibodies to the fetus. However, modern medicine allows for effective minimization of the risk of fetal infection by administering antiviral medications (acyclovir) to the pregnant woman. In justified cases of active genital herpes, the doctor may also recommend a cesarean section.
Untreated herpes during pregnancy and possible consequences for the newborn
Fetal herpes infection is very rare, and the greatest risk comes from untreated genital herpes acquired in the third trimester of pregnancy (perinatal infection). Once the baby is infected, the disease can take one of three forms:
- SEM form: Limited to lesions on the skin, eyes and mouth; has a low mortality rate but requires prompt treatment.
- Infection of the central nervous system (CNS): It can cause encephalitis, seizures and permanent neurological deficits.
- Disseminated form: The most severe form, affecting many organs (liver, lungs, adrenal glands); without treatment, mortality in this case exceeds 80 %.
What to do for cold sores during pregnancy? Treatment, ointment, and home remedies.
Treatment of herpes in pregnant women is based primarily on antiviral pharmacotherapy , the aim of which is to shorten the duration of symptoms and reduce the risk of virus transmission to the child (genital herpes in the 3rd trimester).
Expert advises
If an expectant mother is wondering what herpes treatment is safe during pregnancy, the go-to medication is acyclovir. It is considered a first-line treatment because its safety has been confirmed in numerous studies, and acyclovir does not increase the risk of congenital defects. It can be used after consulting a doctor or pharmacist for herpes during pregnancy, both in the first trimester and in the second or third trimester.
Depending on the clinical situation, the schedule for administering herpes drugs during pregnancy is as follows:
- Primary infection, i.e. the first one in life
Acyclovir is usually administered orally for 7 to 10 days, but the decision regarding treatment of a pregnant woman is made by a doctor, individually assessing the condition of the patient.
- Recurrence of infection
Treatment usually lasts a shorter time, approximately 5 days, and should be initiated as soon as possible—ideally in the prodromal phase, meaning before visible blisters appear. Prodromal symptoms of herpes include burning, tingling, itching, or tenderness of the skin in the area where lesions typically develop. This applies to both recurrences in the genital area and cases where herpes appears on the lips during pregnancy.
- Prevention before delivery, i.e. suppressive treatment
Women with a history of genital herpes are recommended to take acyclovir from the 36th week of pregnancy until delivery. This is especially important if they have a history of genital herpes or herpes in the third trimester of pregnancy.
In Poland, medications used to treat herpes during pregnancy are sometimes prescribed off-label, meaning they are not officially indicated in the package insert. This doesn't automatically mean they are unsafe—it does mean that the doctor makes a decision based on current medical knowledge, the patient's clinical situation, and a balance of benefits and risks.
What can be safely used for herpes during pregnancy, and what ointment is most often recommended by the doctor?
Acyclovir ointment —used as an adjunct to cold sores, it inhibits the virus from multiplying in infected cells. Consult your doctor or pharmacist before using this herpes ointment during pregnancy.
Pracazole protects healthy cells from viral entry, limiting the area of infection and shortening its duration. A doctor may consider it as a topical treatment option for cold sores on the lips during pregnancy.
2% lidocaine gel or ointment helps temporarily relieve pain and burning associated with the rash. These preparations do not treat the underlying cause of the infection, but they may reduce the discomfort associated with herpes symptoms during pregnancy.
Occlusive dressings are an effective home remedy for cold sores during pregnancy. It's recommended that the affected lips be covered with an impermeable dressing (e.g., a special cold sore patch, available at a pharmacy), which reduces the risk of accidentally transferring the virus to other areas, such as intimate areas, via your hands.
What painkillers can be used for herpes during pregnancy?
Expert advises
In addition to applying lidocaine ointment locally to relieve the general symptoms and pain associated with cold sores, expectant mothers can also use paracetamol on an ad hoc basis. However, it's important to remember that home remedies and methods for relieving herpes symptoms during pregnancy should be considered only as a supplement, not a replacement, for antiviral treatment, if deemed necessary by a doctor.
Herpes after birth: can a newborn get infected from his mother or relatives?
Yes, it's possible for a newborn to become infected with herpes after birth. It's estimated that this type of transmission occurs in 5-10% of neonatal herpes cases . Most often, the virus is transmitted through direct contact between the baby and active herpes lesions , such as blisters on the lips, hands, or infected discharge.
Expert advises
The most significant cause is cold sores, a common cold sore experienced by mothers, fathers, siblings, other loved ones, or medical personnel. Kissing a newborn by someone with an active cold sore on the lips is particularly risky. The HSV virus can also be transmitted through touch, especially if the lesions are on the fingers or hands. Breastfeeding is safe because the HSV virus is not transmitted through milk. However, the condition is that there are no active herpes lesions on the breast. If blisters appear on the nipple or areola, the baby should not have contact with this area, and further treatment should be discussed with a doctor.
To reduce the risk of infection in your newborn after birth:
- do not kiss your baby if you have cold lips;
- wash your hands thoroughly before contact with your newborn;
- cover herpes lesions with a dressing if possible;
- Do not allow your child to come into contact with people who have blisters, erosions or fresh lesions on their lips, face or hands.
It is worth remembering that herpes, which is only a nuisance for an adult, can be a serious threat to a newborn.
Therefore, both cold sores on the lips during pregnancy and active cold sores on the lips after childbirth require special caution and consultation with a doctor if there are any doubts about the baby's safety.
This article is for informational purposes only, so if you are pregnant and have experienced symptoms of herpes, are worried about whether herpes is dangerous for the course of pregnancy, and do not know what to use for herpes , consult your doctor.
Bibliography:
- Hammad WAB, Konje JC, Herpes simplex virus infection in pregnancy – An update, European Journal of Obstetrics & Gynecology and Reproductive Biology 2021, vol. 259, pp. 38-45.
- Biało-Wójcicka, Ewelina & Majewski, Sławomir & Łoza, Katarzyna. (2015). Genital herpes – prevention of herpes virus infections. Dermatol Review. 2015, 102, 1–7. DOI: 10.5114/dr.2015.49200
- Jurkowska U., Majewska A., Dmoch-Gajzlerska E., Młynarczyk G., Alphaherpesvirus infection in pregnant women and the risk of perinatal infection of the fetus and newborn, "New Pediatrics" 2011, no. 3, pp. 66–71.
- Straface G., Selmin A., Zanardo V., De Santis M., Ercoli A., Scambia G., Herpes simplex infection during pregnancy, "Dermatology after Diploma" 2013, vol. 4, no. 1, pp. 41–49.
- Anzivino E., Fioriti D., Mischitelli M., Bellizzi A., Barucca V., Chiarini F., Pietropaolo V., Herpes simplex virus infection during pregnancy and in neonates: epidemiology, diagnosis, treatment, and prevention, "Dermatology after Diploma" 2010, vol. 1, no. 2, pp. 45–58.
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