Rubella, also called German measles or 3-day measles, isn’t a problem for most people. It causes a mild fever and rash that go away in a few days. Most kids get vaccinated for it with the MMR (measles-mumps-rubella) or MMRV (which also includes chickenpox) shots. But when you’re pregnant, rubella can be very serious. If you get it in the first 4 months, your baby could have eye, hearing, or heart problems or be born too soon.A positive rubella IgG test result is good—it means that you are immune to rubella and cannot get the infection. This is the most common rubella test done. Negative: This means you are not immune to rubella.