Preeclampsia is a life-threatening complication of pregnancy, diagnosed by the development of high blood pressure and protein in the urine in the latter half of pregnancy. Preeclampsia affects approximately 5 percent of pregnancies, up to 300,000 pregnant women in the U.S. annually. Approximately 75,000 of these women suffer severe maternal outcomes: organ failure, massive blood loss, permanent disability or death; and severe fetal outcomes: prematurity, abnormal fetal growth, and long-term disability or death of their babies.