What are the diagnostic criteria for gestational hypertension (Gestational Hypertension)?

From the Guidelines

Gestational hypertension is diagnosed when a pregnant woman develops persistent de novo hypertension at or after 20 weeks’ gestation in the absence of features of preeclampsia, as defined by the ISSHP classification, diagnosis, and management recommendations for international practice 1. The diagnostic criteria for gestational hypertension include:

• Persistent hypertension that develops at or after 20 weeks’ gestation
• Absence of features of preeclampsia
• No proteinuria or other signs of end-organ damage It's essential to use the correct technique when measuring blood pressure, including having the patient seated with her arm at heart level after resting for 5-10 minutes. The definition of hypertension in pregnancy is based on absolute blood pressure values, with a systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg, as recommended by the European Society of Hypertension and the European Society of Cardiology 1. However, the most recent and highest quality study, published in 2018, provides a clear definition of gestational hypertension, which should be used as the basis for diagnosis and management 1. Key points to consider when diagnosing gestational hypertension include:
• The absence of proteinuria, defined as <300 mg in a 24-hour urine collection or a protein-to-creatinine ratio <0.3
• No evidence of end-organ damage that would suggest preeclampsia
• Regular monitoring of blood pressure throughout pregnancy, with increased frequency after diagnosis
• Gestational hypertension represents a risk factor for developing preeclampsia, which occurs in approximately 25% of women initially diagnosed with gestational hypertension.

From the Research

Diagnostic Criteria for Gestational Hypertension

The diagnostic criteria for gestational hypertension are as follows:

• Systolic blood pressure equal to or greater than 140 mm Hg or diastolic blood pressure equal to or greater than 90 mm Hg, usually on the basis of measurements in office/clinic settings and using various BP devices 2
• New-onset blood pressure elevations of 130 to 139/80 to 89 mm Hg after 20 weeks of gestation in previously normotensive women may also be associated with increased risk for adverse pregnancy outcomes, specifically the development of hypertensive disorders in pregnancy 3
• Gestational hypertension is defined as systolic blood pressure greater than or equal to 140 mm Hg and/or diastolic greater than or equal to 90 mm Hg, occurring beyond the 20th week of amenorrhea and fading before the 42nd day postpartum 4

Classification of Hypertensive Disorders in Pregnancy

Hypertensive disorders of pregnancy are classified into:

• Chronic hypertension diagnosed before pregnancy or before 20 weeks' gestation
• Gestational hypertension diagnosed at equal to or greater than 20 weeks
• Preeclampsia, defined restrictively as gestational hypertension with proteinuria or broadly as gestational hypertension with proteinuria or an end-organ manifestation consistent with preeclampsia 2

Blood Pressure Thresholds

Absolute BP values equal to or greater than 140/90 mm Hg are associated with increased maternal and perinatal risks, particularly with preeclampsia 2 The American College of Cardiology/American Heart Association revised their guidelines for hypertension in the general population in 2017, but hypertension during pregnancy continues to be defined as a systolic blood pressure (SBP) ≥ 140 mmHg and/or a diastolic blood pressure (DBP) ≥ 90 mmHg, measured on two separate occasions 5