Pre-existing hypertension complicating pregnancy, childbirth or the puerperium

**Definition:** A condition affecting pregnant females, caused by previously diagnosed maternal hypertension. This condition is characterised by any complication during pregnancy, childbirth, and the puerperium as a result of a blood pressure reading above 140/90 mmHg prior to the 20th week of pregnancy, or persisting longer than 12 weeks postpartum. Confirmation is by sphygmomanometer.

**Exclusions:** - Pre-eclampsia superimposed on chronic hypertension