VA Â» Office of Public and Intergovernmental Affairs Â» History of Veterans Day. World War I â known at the time as âThe Great Warâ - officially ended when the Treaty of Versailles was signed on June 28, 1919, in the Palace of Versailles outside the town of Versailles, France.
If your blood mixes with Rh-positive blood, your immune system will react to the Rh factor by making antibodies to destroy it. This immune system response is called Rh sensitization. Rh sensitization can occur during pregnancy if you are Rh-negative and pregnant with a developing baby (fetus) who has Rh-positive blood.
Rh is a substance that most people have in their blood (Rh positive) but some people don't (Rh negative). A person who is Rh negative can be exposed to Rh positive blood through a mismatched blood transfusion or during pregnancy when the baby has the opposite blood type. When this exposure happens, the Rh negative blood will respond by making antibodies that will try to destroy the Rh positive blood cells.