Pre-eclampsia is a dangerous complication of the second half of pregnancy, labour or the early puerperium. Placental pre-eclampsia is caused by pathological alterations of the process of placentation in early pregnancy. Maternal pre-eclampsia is provoked by generalised maternal endothelial dysfunction in the second half of gestation. Systemic inflammation can be considered part of every normal pregnancy but is revealed to be more intense in pre-eclamptic women.