Venous thromboembolism complicates 1–2 of every 1000 deliveries. It may manifest as deep vein thrombosis or pulmonary embolism. Pregnancy-associated venous thromboembolism is an important major cause of maternal morbidity and mortality. Prophylaxis and therapy in pregnancy are complicated by the need to take both fetal and maternal well-being into consideration. Risk factors for venous thromboembolism during pregnancy or the puerperium are multiple. They include, but are not limited to, thrombophilia, multiparity, orthopedic injuries, medical comorbidities, prior venous thromboembolism, smoking, gross varicose veins, age, if older than 35, obesity, multiple pregnancy, preeclampsia, cesarean section, prolonged labor, instrumental vaginal delivery, stillbirth, preterm birth, postpartum hemorrhage, hyperemesis gravidarum, ovarian hyperstimulation syndrome, immobility, long periods of hospitalization, and long haul travel. This chapter is a clinical guide that covers prophylaxis and therapy of pregnancy-associated venous thromboembolism, based on evidence-based research and consensus opinion.