Placental Relating to the placenta. An organ within the uterus by which the embryo is attached to the wall of the uterus. It links between the fetal and maternal blood systems to transfer nutrients and waste products. Prophylaxis Any means taken to prevent disease. Rhesus (Rh) factor Antigens that may or may not be present on the surface of red blood cells; people who lack the factor are Rh negative. Incompatibility between Rh negative and positive is the cause of haemolytic disease of the newborn. Rubella German Measles – a mild highly contagious viral infection, mainly of childhood. It can cause malformations in the fetus in early pregnancy. Sickle cell anaemia A hereditary blood disease. Production of an abnormal type of haemoglobin (red blood cells) leading to episodes of anaemia and jaundice and has no cure only able to treat symptoms. Symphysis pubis Joint between the pubic bones of the pelvis.