The "Rh 인자" (Rh factor) is a protein that can be present on the surface of red blood cells. It is an important component in determining a person's blood type, which can be classified as Rh-positive if the protein is present or Rh-negative if it is absent. This classification is crucial for blood transfusions and pregnancy, as incompatible Rh types can lead to serious health issues. In pregnancy, if an Rh-negative mother carries an Rh-positive baby, it can cause complications such as hemolytic disease of the newborn. To prevent this, doctors may administer a medication called Rho(D) immune globulin to the mother during and after pregnancy. Understanding the Rh factor is essential for safe medical practices.