The possibles is knowing the Medical history of the family which can
tell you what hereditary diseases the child boy/girl might be strangely have which could tell the doctors what to look for and how to solve the problem if it can be impossible to be fixed, it will also prepare the parents for what their expectations are for the their child and not be so surprised about the whole situation.
conmon disorders=heart disease, high blood pressure, stroke, certain cancers and more.. other..