Can cytomegalovirus (CMV) harm my baby during pregnancy?

Cytomegalovirus (CMV) is a common virus that is part of the herpes group of viruses, which can also cause cold sores or genital herpes. In most people the CMV does not cause any symptoms and they will not know they are infected.

Infection with the CMV can be hazardous during pregnancy as it can be passed on to the unborn baby and cause problems. This is known as congenital CMV.

Congenital CMV

It is estimated that a third of women who become infected by the CMV for the first time during pregnancy will pass the infection on to their unborn baby. However, CMV is usually only dangerous to the baby if the pregnant mother has not previously had the infection at some point in her life.

Only 10% of unborn babies infected with the CMV virus will go on to develop problems, but unfortunately, these problems can be serious.

They include:

CMV infection can also cause stillbirths if the infection is contracted during the early stages of pregnancy. It is estimated that 10 stillbirths occur in England and Wales every year due to CMV infection.

Preventing CMV infection during pregnancy

As there is no vaccine, or cure, for CMV, it is important to take steps to prevent the chances of you becoming infected during pregnancy.

CMV can be spread through sexual contact so you should use a barrier method of contraception, such as a condom, if you are having sex during your pregnancy.

CMV can also be spread if you have infected saliva or urine on your hands and touch your mouth. The urine and saliva of children under the age of six is particularly at risk of being contaminated with the CMV virus.

Therefore you should:

  • wash your hands with soap and water often, particularly if you have been changing nappies, or you work in a nursery, or day-care centre
  • not kiss children under the age of six on the mouth or cheek – it is better to kiss them on the head, or give them a hug
  • do not share food, drinks, or eating utensils with children who are under the age of six

Read more information about preventing cytomegalovirus.

Further information:

Page last reviewed: 16/04/2013

Next review due: 15/04/2015