Maternal care for oth rhesus isoimmun, first tri, fetus 1

This code signifies ongoing maternal medical management and surveillance during the first trimester of pregnancy due to the mother having antibodies against fetal red blood cell antigens, specifically in cases of rhesus isoimmunization other than the primary D antigen. This condition can lead to hemolytic disease of the fetus and newborn (HDFN), requiring close monitoring of the first fetus.

Apply this code when a pregnant patient in her first trimester is receiving care for rhesus isoimmunization, and the specific antigen involved is not the D antigen (e.g., anti-c, anti-E, anti-Kell). Documentation should clearly indicate the type of rhesus isoimmunization, the trimester, and that the care is for the first fetus.

• Ensure documentation specifies "other rhesus isoimmunization" to differentiate from D isoimmunization.
• Verify the trimester of pregnancy is clearly documented as the first trimester.
• Confirm the code applies to the first fetus; separate codes exist for subsequent fetuses.