Haematologica Reports 2005; 1(issue 10): 34-37[prev][index][next]

The microangiopathy of pregnancy
Armando D’Angelo,¹ Luca Valsecchi^2
1Servizio di Coagulazione ed Unità Ricerca Trombosi, IRCCS H S.Raffaele, Milano, Italy; ²Dipartimento di Ostetricia e Ginecologia, IRCCS H S. Raffaele, Milano, Italy

Hypercoagulabilty occurs in uncomplicated pregnancies, beginning already during the first trimester of gestation. Fibrinogen and factor VIII levels show a progressive increase, accompanied during the second trimester by an increase in VWF levels, while factor XIII levels progressively decrease to 50% during the third trimester.¹ This is consistent with increased in vivo thrombin generation and fibrin formation,² leading to an increased antithrombin turnover.³ Protein S levels show major modifications, reaching 50% levels of normal at term.¹ During pregnancy a condition of acquired protein C resistance is relatively common, due to the increase in factor VIII and V levels and, more important, to their increased state of activation.^4,5 Global fibrinolytic activity is depressed until delivery, mainly due to increased levels of plasminogen activator inhibitors 1 and 2.1 Moderate thrombocytopenia occurs during the last stages of pregnancy and is mainly due to hemodilution.⁶[>Read full article in PDF]