Incidence of venous thromboembolism during pregnancy and the puerperium: a systematic review and meta-analysis

Objective: Women during pregnancy or puerperium have a higher risk of venous thromboembolism (VTE). The reported incidence of pregnancy-associated VTE from literature varied considerably. To summarize the overall incidence of the disease, we conducted this meta-analysis. Methods: We searched PubMed, EMBase and CNKI (China National Knowledge Infrastructure) for studies that reported the incidence of VTE during pregnancy or puerperium. The quality of included studies was assessed using the Newcastle-Ottawa scale and the meta-analysis was conducted using R software and Meta analyst Beta 3.13. Sensitivity analyses were performed to analyze the robustness of the results and publication bias was assessed using Egger's test. Results: Twenty-seven articles met the inclusion criteria. The pooled incidence rate was 1.4% (1.0-1.8%) for VTE, 1.1% (1.0-1.3%) for deep vein thrombosis (DVT) and 0.3% (0.2-0.4%) for pulmonary embolism (PE). The weighted proportion of VTE postpartum was 57.5% and the pooled proportion of right-sided DVT was 27.9%. We noted substantial heterogeneity among individual studies. Conclusions: Women during pregnancy or puerperium are associated with a higher morbidity of VTE. Physicians should be of high vigilance to pregnancy-associated VTE, especially for women postpartum.