Pre-eclampsia is a pregnancy-specific syndrome of unknown aetiology, observed in 3 - 5% of all pregnancies, associated with pathological vascular lesions in multiple organs, activation of the coagulation system, and maternal multisystemic and fetal complications. Clinically, pre-eclampsia is characterised by the onset of hypertension, proteinuria and oedema, usually beginning in the third trimester. Conventionally, antihypertensive agents are the main pharmacological treatment. Recently, some studies have shown that the treatment of pre-eclampsia with antithrombin concentrate corrects the hypercoagulability and improves the fetal status and the perinatal outcome. No clear evidence supports the use of heparin. A conservative treatment of moderate- to- severe pre-eclampsia, based on the administration of antithrombin concentrate, may allow a significant prolongation of pregnancy and a better neonatal outcome, as well as fewer maternal complications.