No blood test can accurately tell if a pregnant or recently pregnant woman has a blood clot. All pregnant women with a suspected clot should continue to have imaging investigations as per current UK guidelines.
This NIHR-funded study recruited 328 pregnant or postpartum women with a suspected blood clot in the lung (pulmonary embolism) or leg (deep vein thrombosis). They had a blood test to measure the levels of 13 biomarkers, such as the D-dimer, to see if they could rule a blood clot in or out. It was hoped that this could reduce the number of women who would need confirmation from a scan, and so decrease their exposure to radiation.
None of the tests were accurate enough. The range of levels for each biomarker overlapped between women with and without a clot.
Hunt BJ, Parmar K, Horspool K, et al. The DiPEP (Diagnosis of PE in Pregnancy) biomarker study: An observational cohort study augmented with additional cases to determine the diagnostic utility of biomarkers for suspected venous thromboembolism during pregnancy and puerperium. Br J Haematol. 2018;180(5):694-704.
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