Preeclampsia superimposed upon chronic hypertension Superimposed preeclampsia is diagnosed when a woman with preexisting hypertension develops new onset proteinuria after 20 weeks of gestation. Women with both preexisting hypertension and proteinuria are considered preeclamptic if there is an exacerbation of blood pressure to the severe range (systolic 160 mmHg or diastolic 110 mmHg) in the last half of pregnancy, especially if accompanied by symptoms or increased liver enzymes or thrombocytopenia.

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