Unsp pre-existing diabetes in pregnancy, second trimester

This code signifies a pregnant patient in her second trimester who has a pre-existing diagnosis of diabetes mellitus, but the specific type of diabetes (e.g., Type 1, Type 2) is not documented. It indicates that the diabetes was present prior to the current pregnancy.

Use this code when a pregnant patient in her second trimester has a documented history of diabetes mellitus that predates the pregnancy, and the medical record does not specify the type of diabetes. Documentation should clearly state "pre-existing diabetes" and the gestational trimester.

• Do not use this code if the type of pre-existing diabetes (e.g., Type 1, Type 2) is specified in the medical record; instead, use the more specific O24.0 or O24.1 codes.
• Ensure the documentation confirms the patient is in her second trimester of pregnancy.
• Always sequence this code as a primary diagnosis when the diabetes is the main reason for the encounter, or as a secondary diagnosis when managing the diabetes during pregnancy.