What is the correct spelling for RJ INCOMPATIBILITY?

When encountering the misspelling "rj incompatibility", it is likely a mistake for "Rh incompatibility". Rh incompatibility occurs when a mother's blood type is Rh-negative and her baby's is Rh-positive. Suggestions for accurate spellings include "Rh incompatibility", "Rhesus incompatibility" or "Rh factor incompatibility".