Categories of Hypertension in Pregnancy

Chronic Hypertension

• Defined as blood pressure (BP) measurement of >140/90 mmHg on 2 occasions prior to pregnancy or before 20 weeks of gestation; also used to refer to hypertension that is diagnosed for the first time during pregnancy and persists beyond 12 weeks postpartum
• Risk of developing preeclampsia is increased

Gestational Hypertension

• Refers to women who develop hypertension without proteinuria after 20 weeks of gestation
  • May correspond to the preproteinuric phase of preeclampsia or recurrence of chronic hypertension abated in midpregnancy
• May progress to preeclampsia
• A diagnosis that is made retrospectively if preeclampsia is not present at the time of delivery and blood pressure returns to normal by 12 weeks postpartum

Preeclampsia/Eclampsia

• Term used to describe condition presenting as hypertension after 20 weeks of gestation, with 1 or more of the following:
  • Proteinuria (>300 mg/24 hours) or protein to creatinine ration >0.3 mg/dL
  • Hematologic disorder: Hemolysis, thrombocytopenia, coagulopathy
  • Liver problems: Elevated liver enzymes and/or severe epigastric or right upper quadrant pain
  • Neurologic signs: Severe headache, persistent visual disturbance (scotoma), hyperreflexia with clonus, seizures (eclampsia)
  • Renal insufficiency: Oliguria or serum creatinine >1.1 mg/dL or increase to twice the normal concentration without other renal disease
  • Pulmonary edema
  • Fetal growth restriction

Preeclampsia Superimposed on Chronic Hypertension

• Also called preexisting hypertension plus superimposed gestational hypertension with proteinuria
• Diagnosis is based on lab tests as above and should be used to distinguish between superimposed preeclampsia and worsening chronic hypertension
• This refers to patients having preexisting hypertension or chronic hypertension with any of the following:
  • New onset proteinuria (≥3 g/24 hours) presents at >20 weeks of gestation
  • Proteinuria in <20 weeks of gestation but with increase in proteinuria
  • Sudden increase in BP that was previously well-controlled
  • Thrombocytopenia
  • Elevated liver enzymes

• Identify high-risk patients with normal blood pressure (BP) in early gestation for close monitoring to prevent preeclampsia
  • Nulliparity
  • Extremes of maternal age (<20 years or >40 years)
  • Chronic hypertension
  • History of hypertension in previous gestation before week 34
  • History of preeclampsia/eclampsia, intrauterine growth restriction (IUGR) or unexplained stillbirth
  • Family history of preeclampsia/eclampsia
  • Preexisting medical conditions [eg diabetes mellitus (DM), collagen vascular diseases, renal vascular or parenchymal diseases]
  • Multifetal pregnancy
  • Obesity or excessive weight gain >1 kg/week
  • Autoimmune disease, eg SLE or antiphospholipid antibody syndrome

• Renal insufficiency
• History of hypertension >4 years
• Hypertension in previous pregnancy
  • An increase in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) to abnormal levels