Preeclampsia—a complication that occurs in about 1 in every 25 pregnancies in the United States—is characterized by high blood pressure and signs of damage to an organ system, most often the liver or kidneys. It usually begins after 20 weeks of pregnancy in women whose blood pressure had previously been normal. In a new study, a multidisciplinary team of Johns Hopkins Medicine researchers has found that the periods before pregnancy and in between pregnancies are key times to address preeclampsia risk factors like obesity, diabetes and hypertension.