Gestational (pregnancy induced) diabetes

Gestational (pregnancy induced) diabetes can occur during the second and third trimester of pregnancy in patients who were not diabetic prior to pregnancy. Gestational diabetes can cause complications in the pregnancy similar to those of pre-existing diabetes mellitus. It also puts the patient at greater risk of developing diabetes after the pregnancy.

Codes for gestational diabetes are in subcategory O24.4, Gestational diabetes mellitus. No other code from category O24, Diabetes mellitus in pregnancy, childbirth, and the puerperium, should be used with a code from O24.4. The codes under subcategory O24.4 include diet controlled, insulin controlled, and controlled by oral hypoglycemic drugs.

If a patient with gestational diabetes is treated with both diet and insulin, only the code for insulin-controlled is required. If a patient with gestational diabetes is treated with both diet and oral hypoglycemic medications, only the code for "controlled by oral hypoglycemic drugs" is required.

Codes Z79.4, Long-term (current) use of insulin, Z79.84, Long-term (current) use of oral hypoglycemic drugs, and Z79.85, Long-term (current) use of injectable non-insulin antidiabetic drugs, should not be assigned with codes from subcategory O24.4. An abnormal glucose tolerance in pregnancy is assigned a code from subcategory O99.81, Abnormal glucose complicating pregnancy, childbirth, and the puerperium.