Maternal care for oth rhesus isoimmun, third tri, fetus 2

This diagnosis code signifies that a pregnant patient is receiving medical management for an Rh incompatibility where the mother's immune system is producing antibodies against the red blood cells of the fetus. Specifically, it indicates that this isoimmunization is due to a cause other than the D antigen (e.g., Kell, Duffy, Kidd, etc.), the pregnancy is in the third trimester, and the code refers to the second fetus in a multiple gestation.

Apply this code when documentation confirms maternal care for an Rh isoimmunization not involving the D antigen, identified in the third trimester of a multiple pregnancy, and specifically addressing the second fetus. Supporting documentation should include serological testing results confirming the presence of non-D Rh antibodies and the gestational age.

• Ensure the specific Rh antigen involved is documented if known, as other codes exist for D isoimmunization.
• Verify the trimester of pregnancy and the specific fetus being managed in multiple gestations.
• Do not confuse with codes for D isoimmunization (O36.01-) or unspecified Rh isoimmunization (O36.099-).