Cerebral veno-sinus thrombosis (CVT) during puerperium may have fatal consequences. A nonspecific clinical picture must be complete with computed tomography of the brain and digital substract angiography of the brain blood vessels, and, once the clinical diagnosis is confirmed, coagulation tests and genetic analysis of the coagulation factor are to be made as well. Genetic polymorphisms associated with thrombophilia such as factor V Leiden, prothrombin G20210A, MTHFR C677T, ACE and PIA1/A2 may be the cause of the hypercoagulability that results in CVT.