Chronic hypertension in pregnancy (CHP) is diagnosed in women whose BP is ≥ 140/90
mm Hg before becoming pregnant (and remains ≥ 140/90 mm Hg during pregnancy)
and in women who develop BP of ≥ 140/90 mm Hg after becoming pregnant but prior to
the 20th week of pregnancy. (Elevated BP in pregnancy that occurs after the 20th week
is diagnosed as gestational hypertension. BP of ≥ 140/90 mm Hg that persists for 12
weeks postpartum or longer is diagnosed as chronic hypertension.) Women with CHP
develop compromised blood flow to the placenta, which can cause fetal complications or
death. Mild CHP is associated with a good prognosis for both the mother and fetus. The
prognosis is less favorable when CHP is severe