Marfan syndrome Marfan syndrome is a birth defect that affects the body's connective tissue. Learn the signs and symptoms of Marfan syndrome and how it's treated.
Rh disease RH factor is a protein on some people's red blood cells. Learn how RH disease affects your baby and how to prevent it.
Rubella and pregnancy Rubella is an infection that causes flu-like symptoms. Rubella during pregnancy can cause problems. Learn about rubella and pregnancy.