Table 2. Classification of the hypertensive disorders of pregnancy
Disorder Comments
Pre-existing (chronic) hypertension This is defined as hypertension that develops either pre-pregnancy or at < 20+0 weeks' gestation
With comorbid condition(s) Comorbid conditions (e.g., pre-gestational type I or II diabetes mellitus or kidney disease)
warrant tighter BP control outside of pregnancy because of their association with heightened
cardiovascular risk.
With evidence of preeclampsia This is also known as superimposed preeclampsia, and is defined by the development of one or
more of the following at ≥ 20 weeks:
● resistant hypertension, or
● new or worsening proteinuria, or
● one or more adverse conditions,* or
● one or more severe complications.*
Severe preeclampsia is defined as preeclampsia with one or more severe complications.
Gestational hypertension This is defined as hypertension that develops for the first time at ≥ 20+0 weeks' gestation.
With comorbid condition(s) Comorbid conditions (e.g., pre-gestational type I or II diabetes mellitus or kidney disease)
warrant tighter BP control outside of pregnancy because of their association with heightened
cardiovascular risk.
With evidence of preeclampsia Evidence of preeclampsia may appear only many weeks after the onset of gestational
hypertension.
Preeclampsia is defined as gestational hypertension with one or more of the following:
● new proteinuria, or
● one or more adverse conditions,* or
● one or more severe complications.*
Severe preeclampsia is defined as preeclampsia with one or more severe complications.
Preeclampsia Preeclampsia may arise de novo. It is defined as gestational hypertension with one or more of the
following:
● new proteinuria, or
● one or more adverse conditions,* or
● one or more severe complications.*
Severe preeclampsia is defined as preeclampsia with one or more severe complications.
Other hypertensive effects†
Transient hypertensive effect Elevated BP may be due to environmental stimuli, e.g., the pain of labour.
White-coat hypertensive effect This is defined as BP that is elevated in the office (sBP ≥ 140 mmHg or dBP ≥ 90 mmHg), but
consistently normal outside of the office (< 135/85 mmHg) by ABPM or HBPM
Masked hypertensive effect This is defined as BP that is consistently normal in the office (sBP < 140 mmHg or dBP
< 90 mmHg), but elevated outside of the office (≥ 135/85 mmHg) by ABPM or repeated HBPM