 - Preeclampsia is a combination of high blood pressure and other potentially life-threatening symptoms. Preeclampsia occurs in up to 10 of pregnancies and is a main cause of maternal and fetal death worldwide. Treatment is often difficult, and so far there is no specific and effective therapy. Researchers have been studying the body systems that regulate blood pressure. They have also studied drugs that can control certain blood chemicals that constrict blood vessels and increase blood pressure. 