Although PE may develop gradually, it often starts abruptly after 20 weeks of pregnancy. The disorder may range from mild to severe. Mild PE occurs in 75% of the cases, whereas severe PE occurs in 25%. Typically, mild PE, severe PE, and eclampsia can be characterized as follows:
Mild PE can be defined as the presence of hypertension (blood pressure
≥140/90) on 2 occasions at least 6 hours apart but without evidence of any organ damage in the patient.
Severe PE is usually considered when the hypertensive patient presents with one or more of the following symptoms or signs:
- Systolic blood pressure of 160 mm Hg or higher or diastolic blood pressure of 110 mm Hg or higher on 2 occasions at least 6 hours apart
- Proteinuria of more than 0.3 g of protein in a 24-hour collection or more than 3+ on 2 random urine samples collected at least 4 hours apart
- Pulmonary edema or cyanosis
- Oliguria (<400 mL in 24 hours)
- Persistent headaches
- Epigastric pain and/or impaired liver function
- Thrombocytopenia
- Oligohydramnios (low amniotic fluid level), decreased fetal growth, or placental abruption
It should be emphasized that both mild and severe forms of PE can exist without proteinuria! Ten percent of individuals with other symptoms and signs of PE and 20 percent of those diagnosed with PE show no evidence of proteinuria. In the absence of proteinuria, the presence of hypertension, along with other signs and symptoms, is still suggestive of PE.
Eclampsia: If preeclampsia-associated seizures develop and cannot be attributable to any other disorder, then the disorder is called eclampsia.
