What are the diagnostic criteria for gestational hypertension and preeclampsia?

From the Guidelines

Gestational hypertension is diagnosed when a pregnant woman develops new-onset hypertension (blood pressure ≥140/90 mmHg) after 20 weeks of gestation without proteinuria or other features of preeclampsia, as defined by the ISSHP classification, diagnosis, and management recommendations for international practice 1. The diagnostic criteria for gestational hypertension and preeclampsia are crucial for appropriate management decisions, including timing of delivery, antihypertensive therapy, and seizure prophylaxis with magnesium sulfate when indicated.

• Gestational hypertension is characterized by new-onset hypertension after 20 weeks of gestation without proteinuria or other features of preeclampsia.
• Preeclampsia requires new-onset hypertension after 20 weeks of gestation plus either proteinuria (≥300 mg in 24-hour urine collection or protein/creatinine ratio ≥0.3) or evidence of end-organ damage, as recommended by the ISSHP 1. Key features of preeclampsia include:
• New-onset hypertension after 20 weeks of gestation
• Proteinuria (≥300 mg in 24-hour urine collection or protein/creatinine ratio ≥0.3)
• Evidence of end-organ damage, such as thrombocytopenia, renal insufficiency, liver involvement, pulmonary edema, cerebral or visual symptoms, or fetal growth restriction Regular monitoring of blood pressure, proteinuria, and maternal and fetal well-being is essential throughout pregnancy once these conditions are diagnosed, as emphasized by the ISSHP recommendations 1. The ISSHP recommends that all women with chronic hypertension in pregnancy have baseline tests performed at first diagnosis, including a full blood count, liver enzymes, serum creatinine, electrolytes, and uric acid, as well as urinalysis and microscopy 1.

From the Research

Diagnostic Criteria for Gestational Hypertension and Preeclampsia

The diagnostic criteria for gestational hypertension and preeclampsia are as follows:

• Gestational hypertension is defined as new-onset blood pressure elevations of 130 to 139/80 to 89 mm Hg after 20 weeks of gestation in previously normotensive women 2.
• Preeclampsia is defined as hypertension in association with proteinuria, thrombocytopenia, impaired liver function, renal insufficiency, pulmonary edema, or new-onset cerebral or visual disturbances 3, 4.
• Severe features of preeclampsia include a systolic blood pressure of at least 160 mm Hg or a diastolic blood pressure of at least 110 mm Hg, platelet count less than 100 × 10^3 per µL, liver transaminase levels two times the upper limit of normal, a doubling of the serum creatinine level or level greater than 1.1 mg per dL, severe persistent right upper-quadrant pain, pulmonary edema, or new-onset cerebral or visual disturbances 4.

Key Differences Between Gestational Hypertension and Preeclampsia

• Gestational hypertension is characterized by new-onset hypertension after 20 weeks of gestation, while preeclampsia is characterized by hypertension and one or more of the following: proteinuria, thrombocytopenia, impaired liver function, renal insufficiency, pulmonary edema, or new-onset cerebral or visual disturbances 4, 5.
• Venous hemodynamic dysfunction is a feature of preeclampsia but not of gestational hypertension 5.

Management and Monitoring

• Women with hypertensive disorders should be monitored as inpatients or closely at home for 72 hours postpartum 4.
• Preeclampsia without severe features can be managed with twice-weekly blood pressure monitoring, antenatal testing for fetal well-being and disease progression, and delivery by 37 weeks' gestation 4.
• Preeclampsia with any severe feature requires immediate stabilization and inpatient treatment with magnesium sulfate, antihypertensive drugs, corticosteroids for fetal lung maturity if less than 34 weeks' gestation, and delivery plans 4.