Preeclampsia is defined as new onset hypertension and proteinuria after 20 weeks of gestation. It can progress to eclampsia, which is characterized by seizures in addition to the symptoms of preeclampsia. Magnesium sulfate is the primary treatment for preventing seizures in women with eclampsia, as it is more effective than other anticonvulsants like diazepam or phenytoin. Care of women with eclampsia involves prevention of seizures, management of hypertension, and evaluation for prompt delivery of the fetus once the mother is stabilized.