Pharmacological Thromboprophylaxis during Pregnancy and the Puerperium: Recommendations from Current Guidelines and their Critical Comparison

Venous thromboembolism (VTE) is one of the leading causes of maternal deaths world-wide. Due to the increasing number of pregnant women with risk factors, the incidence of VTE has risen over the past decades. Mortality and morbidity of VTE are potentially preventable, since more than two-thirds of these women have identifiable risk factors and may benefit from appropriate thromboprophylaxis. The cornerstones for prevention of VTE are the individual and careful assessment of preexisting and new-onset/transient risk factors during pregnancy as well as before and after delivery and a risk-stratified pharmacological thromboprophylaxis. Current recommendations for thromboprophylaxis must rely on consensus statements and expert opinions. The recently published German AWMF-Guideline 003/001 and the Green-top Guideline No. 37a from the Royal College of Obstetricians and Gynaecologists (RCOG) are dis-cussed. The RCOG Guideline recommends antenatal thromboprophylaxis in women with previous VTE, high-risk thrombophilia or in the presence of >= 4 risk factors from the beginning of pregnancy, in women with 3 current risk factors from 28 weeks of gestation. After delivery women with intermediate risk should receive prophylactic LMWH for at least 10 days and women with high risk for 6 weeks postnatally. All women who have had an elective caesarean section and who have >1 additional risk factor should be given prophylactic NMH as well as all women who have had a caesarean section in labour or an emergency caesarean section. At the onset of labour, in case of any vaginal bleeding, prior to scheduled labour induction or at least 12 h before an elective caesarean section, antenatal LMWH prophylaxis should be discontinued. LMWH prophylaxis can be continued 4-6 h after vaginal delivery and 6-12 h after caesarean delivery when women do not have an increased risk of haemorrhage. Current guidelines recommend weight-based LMWH.