Diagnostic algorithm for suspected deep venous thrombosis in pregnancy

DVT: deep vein thrombosis; CUS: compression ultrasound.

* Refers to patients with an initial negative CUS in whom clinical suspicion remains that is not high. Refer to UpToDate topics on DVT in pregnancy.

¶ Alternative imaging techniques include doppler ultrasound of the iliac vein and contrast or magnetic resonance venography.

Δ Consideration can be given to measuring a D-dimer level using enzyme linked immunosorbent assay (ELISA) or red blood cell agglutination (SimpliRED). A D-dimer level <500 ng/mL is considered negative and no further testing is needed. A D-dimer level >500 ng/mL is not diagnostic and has no value in directing further testing in pregnant patients.