Maternal care for oth rhesus isoimmun, first trimester, oth

This code signifies antenatal care provided to a pregnant patient in her first trimester due to the presence of rhesus isoimmunization, specifically when the type of isoimmunization is not specified as ABO or other specified types. It indicates that the isoimmunization affects a fetus other than a single fetus or multiple fetuses where the specific fetus is identified.

Use this code when documentation confirms maternal care for rhesus isoimmunization during the first trimester, and the type of isoimmunization is not otherwise classified. This applies when the medical record indicates the isoimmunization affects a fetus in a multiple gestation pregnancy, but the specific fetus is not identified, or in cases where "other fetus" is explicitly documented. Documentation should clearly state "first trimester" and "rhesus isoimmunization, other."

• Ensure the documentation specifies "first trimester" for accurate trimester assignment.
• Distinguish from O36.01- (ABO isoimmunization) and O36.0A- (other specified rhesus isoimmunization).
• Confirm that the documentation supports "other fetus" in cases of multiple gestations or when the specific fetus is not identified.