| O24.01 | Pre-existing type 1 diabetes mellitus, in pregnancy | NON-BILLABLE CODE |
| O24.011 | Pre-existing type 1 diabetes mellitus, in pregnancy, first trimester | BILLABLE CODE |
| O24.012 | Pre-existing type 1 diabetes mellitus, in pregnancy, second trimester | BILLABLE CODE |
| O24.013 | Pre-existing type 1 diabetes mellitus, in pregnancy, third trimester | BILLABLE CODE |
| O24.019 | Pre-existing type 1 diabetes mellitus, in pregnancy, unspecified trimester | BILLABLE CODE |
| O24.02 | Pre-existing type 1 diabetes mellitus, in childbirth | BILLABLE CODE |
| O24.03 | Pre-existing type 1 diabetes mellitus, in the puerperium | BILLABLE CODE |
