| O10.01 | Pre-existing essential hypertension complicating pregnancy | NON-BILLABLE CODE |
| O10.011 | Pre-existing essential hypertension complicating pregnancy, first trimester | BILLABLE CODE |
| O10.012 | Pre-existing essential hypertension complicating pregnancy, second trimester | BILLABLE CODE |
| O10.013 | Pre-existing essential hypertension complicating pregnancy, third trimester | BILLABLE CODE |
| O10.019 | Pre-existing essential hypertension complicating pregnancy, unspecified trimester | BILLABLE CODE |
| O10.02 | Pre-existing essential hypertension complicating childbirth | BILLABLE CODE |
| O10.03 | Pre-existing essential hypertension complicating the puerperium | BILLABLE CODE |
