Herpes and Pregnancy: Essential Facts

Women who have genital herpes can pass on the infection to the baby.

This happens at the time of birth if the baby comes into contact with the virus as it rubs against the woman's birth canal and genitals.

Herpes in newborn babies (neonatal herpes) can be a very serious medical condition.

Neonatal herpes most commonly appears as a general infection which may affect the lungs, liver, and brain of the baby. There is usually a rash, but some infants with herpes do not develop one. There is a high death rate, even with treatment.

Fortunately, neonatal herpes is very rare.

In Australia, it occurs only once in every 11,000 to 15,000 births.

The risk of neonatal herpes is highest for women who have never had genital herpes or cold sores.

If a woman comes into contact with the herpes simplex virus for the first time during a pregnancy, she is more likely to pass it on to the baby because:

• She will shed more viruses for a longer time than if she already had herpes before the pregnancy.
• There are no pre-existing antibodies in the baby's circulation to fight off the virus. Women who have already had herpes before the pregnancy transfer the herpes antibodies to the foetus, giving it some immunity against a further recurrence of herpes.

If you are pregnant and have a history of genital herpes, you must tell your obstetrician.

There is still a small risk of the baby coming into contact with the herpes virus. The obstetrician will be able to assess the risk and provide suitable treatment to minimise it.

You probably will not need to have a Caesarean section, unless there is an active outbreak when you go into labour.

If there is an active outbreak a Caesarean section will reduce the risk of the baby rubbing against the virus as it is born.

If you are pregnant and have never had genital herpes but your partner has, it's important to avoid infection.

• Avoid sexual contact whenever your partner has signs of herpes.
• Your partner should not perform oral sex if they have any signs of cold sores.
• Partners should use condoms for all sexual contact.
• Your partner may wish to consider anti-viral treatment to further reduce the risk of passing on the virus.

If you contract genital herpes for the first time when you are pregnant, you may need to take anti-viral medication.

You will not necessarily need a Caesarean section. It depends how late in the pregnancy you contract herpes.

If you have not had any outbreaks of herpes during the pregnancy, the baby should not require any special tests or treatment after birth.

However, you should look out for warning signs such as lethargy, irritability, poor feeding or sores or blisters on the skin.