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.
How Does Rh Sensitising Happen During Pregnancy. During pregnancy, the motherâs and babyâs blood systems are separate. However, during pregnancy, labour or birth, a small number of red blood cells from the baby can cross the placenta and enter the motherâs blood. This can also happen if the mother experiences: 1  Amniocentesis (sampling of amniotic fluid via a needle inserted through the abdomen) 2  Chorionic villus sampling (sample from the placenta via needle inserted into the abdomen or through the cervix) 3  Any bleeding during pregnancy. 4  Any blunt trauma to the abdomen during pregnancy.