Pre-eclampsia is estimated to affect about 5% of deliveries while eclampsia affects about 1.4% of deliveries. In the developed world rates are about 1 in 2,000 deliveries due to improved medical care. Hypertensive disorders of pregnancy are one of the most common causes of death in pregnancy. They resulted in 46,900 deaths in 2015. Around one percent of women with eclampsia die. The word "eclampsia" is from the Greek term for lightning. The first known description of the condition was by Hippocrates in the 5th century BC.