Pulmonary embolism (PE) has been identified as the most important cause of direct maternal mortality in the UK today and has been extensively studied as part of the ongoing Confidential Enquiry into Maternal Deaths.
In contrast, non-fatal PE in pregnancy has not been extensively studied.
This study identified 143 women with antenatal PEs, representing an estimated incidence of 1.3 per 10,000 maternities (95% CI 1.1-1.5).
70% of women had identifiable classical risk factors for thromboembolic disease.
The main risk factors for PE were multiparity and obesity.
Five women died (case fatality 3.5%, 95%CI 1.1-8.0%).
This demonstrates that significant severe morbidity from thromboembolic disease underlies the maternal deaths from PE in the UK.
The study revealed some cases where thromboprophylaxis was not provided according to national guidelines and there may be scope for further work on guideline implementation.