[Clinical Confusion Concerning Increased D-Dimer Value during Pregnancy]

Plasma D-dimer, a special cross-linked fibrin derivative, is produced when fibrin is degraded by plasminase. During pregnancy, D-dimer increases along with the increase of gestational age, and the reference value of plasma D-dimer (≤0.5 mg/L) traditionally used for the screening of venous thrombosis in the normal population is not applicable to the pregnant population. Due to the lack of uniform D-dimer detection methods or measurement units, there is currently no unified D-dimer reference values for pregnancy or puerperium. Each region or laboratory should establish its own pregnancy D-dimer reference value for different gestational weeks through blood coagulation function testing of large numbers of samples of different gestational periods. More and more studies have been conducted to investigate the association between D-dimer and venous thromboembolism (VTE) during pregnancy, gestational hypertensive disorders (GHD) and pregnancy outcome. We reviewed, herein, the generation and measurement of D-dimer, the reference values of D-dimer during normal pregnancy, and the association between D-dimer and some pathological pregnancies, intending to help clinicians develop a more thorough understanding of D-dimer during pregnancy.