Cytomegalovirus is the most common transmitted virus from a pregnant woman to her unborn child. Most CMV infections are “silent” and harmless, but in pregnant women, CMV can be transmitted to the fetus, with sometimes devastating effects to the unborn baby and newborn. One out of every 150 babies is born with congenital CMV. If a pregnant woman is infected with CMV, she can pass it to her developing baby. This is called congenital CMV, and it can cause birth defects and other health problems. This is more likely to happen if you have a frst-time (primary) CMV infection while pregnant but can also happen if you have a subsequent infection during pregnancy. Between 50 to 80 percent of women of childbearing age have caught CMV and between 1 and 5 percent of pregnant women will catch CMV for the first time during their pregnancy.

In UK pregnant women are not routinely tested for CMV infection. However, it is possible to determine in your blood if you have had the infection prior the pregnancy and have developed antibodies or if you are at risk of primary CMV infection.