The Indirect Coombs Test, also known as the Indirect Antiglobulin Test (IAT), is used to detect antibodies against the Rh factor in a mother's blood. A positive result indicates the presence of antibodies that could potentially attack red blood cells, which may pose risks to both the mother and the baby. This test is commonly performed early in pregnancy and before blood transfusions to assess compatibility and prevent complications, such as hemolytic disease of the newborn.