Pharmacologic thromboprophylaxis following cesarean delivery-what is the evidence? A critical reappraisal

Venous thromboembolism (VTE) is a severe complication associated with cesarean delivery (c.d.). The risk of VTE has been estimated to be 2-4-fold higher compared to vaginal delivery and appears independent of other risk factors. Pharmacologic thromboprophylaxis after c.d. represents a daily challenge for obstetricians and is a common practice in many countries such as in Germany. However, the evidence of thromboprophylaxis efficacy is based on only four randomized controlled trials and one prospective cohort study. Risk assessment models to predict VTE after c.d. have not adequately been validated. According to meta-analyses pharmacologic thromboprophylaxis was not associated with a significant reduction in the risk of VTE but is associated with an increased risk of bleeding and hematomas compared to placebo. Due to the lack of evidence current guidelines differ markedly regarding recommendations on post-cesarean pharmacologic thromboprophylaxis. Most guidelines recommend no pharmacologic thromboprophylaxis after elective c.d. in the absence of additional VTE risk factors. In case of additional risk factors associated with elective c.d. as well as in case of emergency c.d. pharmacologic prophylaxis is advised for 7-10 days after delivery, and for at least 6 weeks after c.d. in high-risk patients. In view of the great number of various risk factors, the challenge not recognizing all risk factors timely and the low incidence of serious complications associated with the use of low molecular weight heparin (LMWH), we consent with others to suggest universal LMWH prophylaxis following c.d. rather than a selective being aware that universal LMWH prophylaxis is associated with significantly higher costs.