A case is presented of a primigravida with transient diabetes insipidus, gestational hypertension, and multiple seizures resistant to magnesium sulfate and diazepam. After addition of phenytoin, no further seizures occurred. Transient diabetes insipidus in pregnancy has been previously associated with hypertension, liver dysfunction, and fetal distress. Considered with previous cases, it is suggested that seizures may frequently be part of this syndrome.