Pre-existing essential htn comp pregnancy, first trimester

This code identifies a patient with a pre-existing diagnosis of essential hypertension who is currently pregnant and in her first trimester. It signifies that the chronic high blood pressure existed prior to conception and is now a complicating factor in the current pregnancy.

Apply this code when documentation clearly states a history of essential hypertension (e.g., "chronic hypertension") in a pregnant patient during the first trimester (up to the end of the 13th week of gestation). Supporting documentation includes physician notes confirming the pre-existing nature of the hypertension and the current gestational age.

• Always confirm the trimester of pregnancy; different codes exist for subsequent trimesters.
• Distinguish from gestational hypertension, which develops during pregnancy in a previously normotensive patient.
• Sequence this code as a primary diagnosis when the hypertension is the focus of the encounter, or as a secondary diagnosis when another pregnancy complication is primary.