Maternal care for oth isoimmun, first trimester, fetus 4

This code signifies antenatal care provided to a pregnant patient in her first trimester due to an isoimmunization other than Rh, ABO, or other specified types. This condition involves the mother's immune system producing antibodies against fetal red blood cell antigens, potentially leading to hemolytic disease of the fetus and newborn. The "fetus 4" designation indicates that the care is specifically for the fourth fetus in a multiple gestation pregnancy.

Apply this code when documentation clearly indicates maternal care for an unspecified or "other" type of isoimmunization (e.g., Kell, Duffy, Kidd, MNSs, P) during the first trimester of a pregnancy involving quadruplets or higher-order multiples, and the care is directed at the fourth fetus. Supporting documentation should include serology results confirming the presence of irregular antibodies and a sonogram or other imaging confirming the number of fetuses and gestational age.

• Always confirm the specific type of isoimmunization; if more specific codes (e.g., O36.11- for Rh, O36.12- for ABO) are available, use those instead.
• Verify the trimester of pregnancy and the specific fetus being managed in multiple gestations. Incorrect trimester or fetus number is a common error.
• This code is for maternal care; do not use it for fetal conditions or complications directly.