Hypertension occurring during pregnancy needs to classified correctly in order to guide medical therapy.
Chronic hypertension is defined as a blood pressure > 140/90 mm Hg in
(1) a nonpregnant female
(2) before 20 weeks of gestation
(3) persisting more than 6 weeks post-partum
Late or transient hypertension:
(1) development of hypertension during pregnancy without other signs of pre-eclampsia
Pre-eclampsia:
(1) onset of hypertension at greater than 20 weeks of gestation with proteinuria and/or edema
(2) hypertension: blood pressure greater than 140/90 mm Hg on more than 2 occasions greater than 6 hours apart
(3) proteinuria: greater than 300 mg per 24 hours or urine dipstick greater than 1+ on 2 occasions more than 6 hours apart
(4) hyperuricemia greater than 5 mg/dL
Chronic hypertension with superimposed pre-eclampsia:
(1) exacerbation of chronic hypertension greater than 30 mm Hg systolic or 15 mm Hg diastolic, plus the appearance of significant proteinuria
Severe pre-eclampsia - when one or more of the following is present:
(1) blood pressure greater than 160 mm Hg systolic or 110 mm Hg diastolic on 2 occasions more than 6 hours apart
(2) proteinuria greater than 5 grams per 24 hours or 3-4+ by dipstick
(3) oliguria less than 400 mL per 24 hours
(4) cerebral or visual disturbances
(5) pulmonary edema or cyanosis
Eclampsia is defined as the presence of seizures in a patient with preeclampsia.
