ABSTRACT
EPIDEMIOLOGY AND INCIDENCE VTE is one of the leading causes of pregnancy-related maternal morbidity and mortality in high-income countries [6]. Fatal PE accounts for 9.8% of all pregnancy related deaths in the United States [7]. Due to physiological and anatomical changes normally associated with pregnancy, the risk of VTE in women during pregnancy and immediately postpartum is higher than women who are the same age and not pregnant. The risk of VTE is increased fivefold during pregnancy and 60-fold during the first three months after birth [8]. A systematic review to evaluate the risk of VTE during the postpartum period demonstrated a substantially higher risk during the first six weeks postpartum with a gradual decline with every week after delivery; however, it is not entirely clear from these data exactly when a woman’s risk of VTE returns to baseline levels [9]. This risk might persist until at least 12 weeks postpartum [10]. Although the relative risk of VTE is greatly increased, the absolute risk is estimated at around one to two in 1000 pregnancies [11]. Although much of the evidence suggests an incidence is equally distributed throughout all trimesters, a recent study suggested an exponential increase in the risk across the duration of pregnancy [12]. The highest risk is in the puerperium likely because of the addition of trauma to the pelvic vessels during delivery. Unlike nonpregnant women, in which distal DVT is more common, the anatomic distribution of DVT in pregnant women differs from that for nonpregnant patients. In addition to what was previously known-that left-sided DVT is more common in pregnancy-this study also found that proximal DVT restricted to the femoral or iliac veins is also more common (>60% of cases) [13]. PE occurs in 15% of untreated DVTs with a mortality rate of 1% and in 4.5% of treated DVTs with a mortality rate of 1% [14]. Death from PE occurs in about every 1.1-1.5 per 100,000 pregnancies [15].
