DefinitionCongenital rubella is a group of physical problems that occur in an infant when its mother is infected with the virus that causes German measles.Causes, incidence, and risk factorsCongenital rubella is caused by the destructive action of the rubella virus on the fetus at a critical time in development. The most critical time is the first trimester (the first 3 months of a pregnancy). After the fourth month, the mother's rubella infection is less likely to harm the developing fetus.The rate of congenital rubella has decreased dramatically since the introduction of the rubella vaccine.Risk factors for congenital rubella include:Not getting the recommended rubella immunizationContact with a person who has rubella (also called the 3-day measles or German measles)Pregnant women who ar