Treatment for CMV in Pregnancy

Evidence suggests that the use of a drug called valacyclovir (antiviral treatment) could be helpful in reducing the risk of the CMV infection passing from the mother to her baby during pregnancy or to reduce the risk of severe problems in babies that have been infected.   A recent randomised control trial showed valacyclovir reduced the rate of fetal infection by 71%.  You should arrange a consultation with a specialist to discuss this option as evidence is still emerging and practice and guidelines are likely to vary.  This treatment is also not suitable in all circumstances.

A treatment called Hyperimmune Globulin (HIG) aims to reduce the risk of the transmission from mother to baby and to reduce the severity of symptoms in babies that might have been infected.  However, despite the fact that some small-scale studies reported possible, larger good quality studies have shown that it is not beneficial and in fact it might harm and HIG is therefore not offered in the UK or other countries as routine practice.  Research is ongoing in this area.

Some babies do have more severe symptoms when they are born. Diagnosis in pregnancy can help to ensure that your new-born baby is diagnosed quickly and gets the support that he or she needs. You should see a fetal medicine specialist who will perform a detailed ultrasound of the baby.  The fetal medicine specialist might arrange additional ultrasound scans and other tests, such as MRI of the baby’s brain in order to look for possible harm caused by the CMV virus.  These tests should help the fetal medicine specialist to tell you whether the baby is likely to have problems caused by CMV after birth or not.

CMV Action can give you emotional support during this uncertain time.

Freephone: 0808 802 0030Email: info@cmvaction.org.uk

Organisations such as Antenatal Results and Choices (ARC) can also offer professional support to help you through difficult decisions in pregnancy.

Treatment for Babies and Children

Treatment for babies and children affected by congenital CMV will depend on many factors, including whether they have symptoms at birth, how serious these symptoms are, whether there is hearing loss, if there are changes on the scans of the brain (ultrasound or MRI), and when diagnosis is made.  Treatment is not recommended for every baby as there is no evidence that it is helpful in all babies.

Antiviral drugs, such as ganciclovir and valganciclovir, can be used to treat babies and should be started within the first month of their life.  Ganciclovir is given intravenously (into a vein via a ‘drip’) and would be the drug used for babies who are not able to take all their feeds by mouth, for example in premature babies.  Valganciclovir is given by mouth and would be used for babies who are feeding normally.

The main benefit is to preserve hearing and prevent progression of hearing loss associated with congenital CMV.  Also, there may be modest benefits in reducing the impact of congenital CMV infection on the neurodevelopment of the child, in particular improving communication skills.  Emerging evidence shows that even when babies have less severe symptoms, treatment can be of benefit. You should discuss all treatment options with your baby’s doctor including any risks associated with anti-viral treatment.

Depending on the treatment given and the severity of their symptoms, your baby may need to stay in hospital for the first part of their treatment.  They will be closely monitored for any side effects and risks.  The length of treatment will be discussed with you; however, it is normally given for a total of six months.

When should anti-viral treatment be used?

Anti-viral treatment is recommended for babies if CMV infection has affected the central nervous system, including their hearing, or a significant effect on other organs. Treatment is normally only recommended to start within the first month of life, as currently we do not have the evidence to support starting treatment later than this.  A recent small clinical trial reported that there is no positive effect of antivirals in older babies and children. However, this is an area to discuss with your doctor, as discretion may be used.  The goal of anti-viral treatment is to reduce the amount of active virus so that the baby is able to control the infection with his or her own immune system.

Should asymptomatic babies be treated?

Most babies born with congenital CMV are asymptomatic and do not have any symptoms at birth. However, by the age of five, around 15% may go on to develop hearing loss. Anti-viral treatment is not recommended for all newborns because at present there is no evidence of benefit unless the baby has hearing loss or CMV has affected the central nervous system.   There is currently no evidence that anti-viral treatment is of benefit for children who develop hearing loss later in childhood.  However, studies are currently being carried out to understand more about this.

What are the benefits of antiviral treatment?

Anti-viral treatment may help to prevent hearing loss or stop hearing loss getting worse and improve the development of communication. These benefits have been observed in two year olds whose central nervous system (brain and spinal cord) had already been affected by CMV when they were diagnosed.

What are the side effects of treatment?

The most common side effect of anti-viral treatment is a decrease in the number of white blood cells that help fight infection. Around one in five babies will experience this side effect, most commonly in the first few weeks after starting anti-viral treatment. Less commonly, anti-viral treatment may cause a reduction in the number of platelets (the cells that help the blood clot)  in the blood (1 in 100).  Although rare, the liver can also be affected in some cases. Blood tests are required to closely monitor the blood cells and function of the liver.If any of these tests suggest a problem, then treatment may be stopped or decreased.  Your baby may be prescribed other medication to help improve the number of white blood cells.  CMV virus levels will also be monitored during treatment through blood, urine and saliva tests.  Your medical expert will help explain the side effects for the dose of medication.

The decision to start anti-viral treatment is not straightforward and will not be appropriate for all babies. The potential benefits of treatment need to be considered alongside the potential side effects of treatment.  It is important that you have the opportunity to discuss the decision about whether to start anti-viral treatment with a doctor who has experience in treating babies with congenital CMV, such as a paediatric infectious diseases specialist.  CMV Action can help you find a specialist.

Should I breast feed my baby?

CMV can be passed through breast milk. However, if your baby is born full term, and you have CMV, they will not develop any problems if you are breast feeding.

Babies who have been infected with CMV in the womb may also be re-infected with a new strain of CMV in the breast milk. It is thought that this does not cause further problems. The benefits of breast milk are numerous and well documented and if you wish to breast feed your baby you should be encouraged to continue.

Some parents are concerned that if they breastfeed, they will pass the virus to their baby and this will affect the newborn test results.  Whilst the CMV virus can be passed through breast milk, postnatally acquired infection will not show up in this test for the first 21 days.  This is another reason why it is essential that a baby is tested within the first 21 days to confirm whether there is a congenital infection.

Should I continue to breast feed if my baby is being treated with anti-viral medication?

Yes, you can continue to breast feed if your baby is being treated with anti-viral medication.  The benefits of breast milk for all babies are numerous and well documented and if you wish to breast feed your baby you should be encouraged to continue.