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.
If you are Rh-negative, you may develop antibodies to an Rh-positive baby. If a small amount of the babyâs blood mixes with your blood, which often happens, your body may respond as if it were allergic to the baby. Your body may make antibodies to the Rh antigens in the babyâs blood.ensitization can occur any time the fetusâs blood mixes with the motherâs blood. It can occur if an Rh-negative woman has had: 1  A miscarriage. 2  An induced abortion or menstrual extraction. 3  An ectopic pregnancy.