Genital herpes in pregnancy
Genital herpes is a long-term condition, with symptoms which can usually be effectively controlled using antiviral medicines. In pregnancy, there can be a small risk of complications from genital herpes. It is most likely to cause problems if you contract it for the first time during pregnancy.
What is genital herpes?
Genital herpes is a condition which leads to painful blisters or ulcers (similar to cold sores) on the genitals. In women it can affect the skin in and around the vagina, the vulva (lips around the vagina) and the opening of the bladder (urethra).
Genital herpes is caused by a virus called the herpes simplex virus (HSV). This virus also causes infections in other part of the body, such as coldsores and whitlows.
Genital herpes is quite common and can be passed to both men and women through intimate sexual contact. It is therefore referred to as a sexually transmitted infection (STI). Even if someone with genital herpes does not have any symptoms, it is possible for them to pass the condition on to a sexual partner. At least 8 out of 10 people who carry the virus are unaware that they have been infected.
Genital herpes is a chronic (long-term) condition. Most people who have it will notice symptoms four or five times in the first two years after being infected. The virus stays in your body and can become active again at any time. However, the attacks get less frequent and the condition becomes less severe over time.
You should tell your midwife at the first appointment if you or your partner have ever had the herpes simplex virus. Generally speaking, if you get genital herpes before you become pregnant, your immune system will provide protection to your baby when you become pregnant. Recurrent episodes of genital herpes during pregnancy do not affect the baby.
If you’re pregnant when you have genital herpes for the first time, you may be treated with antiviral medicine (aciclovir), to clear up the infection before your baby is born. Your midwife or GP may refer you to a genito-urinary specialist for tests and treatment.
If you get genital herpes for the first time during the first three months of pregnancy, there’s a small risk of miscarriage. However, most women with genital herpes have healthy babies and a normal vaginal birth.
If you get genital herpes for the first time later in your pregnancy your immune system may not be able to protect your baby. A pregnant woman can pass the infection on to the baby during birth. The risk of passing on a newly caught infection to the baby during vaginal birth is about 4 in 10 (40%).
If a baby becomes infected at birth, the condition is called neonatal herpes. Neonatal herpes can cause infection in the baby’s skin, eyes, brain and other organs. The condition is rare in the UK, affecting only 1-2 in every 100,000 babies born.
If you have active sores when your labour starts, your doctor or midwife will discuss the birth with you, so you can decide how you want your baby to be born. It’s likely you’ll be offered a caesarean section for the birth, to reduce contact with active sores.
Page last updated: 25 January 2013
NCT's helpline offers practical and emotional support in all areas of pregnancy, birth and early parenthood: 0300 330 0700. We also offer antenatal courses which are a great way to find out more about birth, labour and life with a new baby.
NHS Choices offers information on the risks of genital herpes in pregnancy.
The Royal College of Obstetricians and Gynaecologists publish a leaflet Genital herpes in pregnancy: information for you.