Final answer:
The mother's Rh factor should be determined before conception to prevent hemolytic disease of the newborn (HDN) caused by Rh incompatibility. Rh factor incompatibility between mother and fetus can lead to a type II hypersensitivity hemolytic reaction. Regular screening and treatments are available to prevent HDN caused by Rh incompatibility.
Step-by-step explanation:
The mother's Rh factor should be determined before conception. Rh factor incompatibility between mother and fetus can cause a type II hypersensitivity hemolytic reaction known as hemolytic disease of the newborn (HDN). This occurs when an Rh- woman carries an Rh+ baby to term, and the mother's immune system is exposed to Rh+ fetal red blood cells. To prevent HDN, the Rh factors of prospective parents are regularly screened, and treatments have been developed to prevent HDN caused by Rh incompatibility.