Reference intervals for coagulation parameters in non-pregnant and pregnant women

Abstract

Established reference intervals (RIs) of coagulation parameters generally based on the general population are not applicable to specific women. In order to accurately evaluate the coagulation status of non-pregnant women and pregnant women, specific RIs should be established. Our study recruited 465 non-pregnant women and 1972 pregnant women aged 20–45 years. Eight tests including antithrombin (AT), protein C (PC), free protein S (fPS), lupus anticoagulant (LA), D-dimer, fibrin/fibrinogen degradation products (FDP), coagulation factor VII (FVII), and factor VIII (FVIII) were performed on ACL TOP automated coagulation instrument. The RIs for these tests were established in non-pregnant and pregnant women at different gestational weeks. Compared to the non-pregnant group, the medians of AT and fPS were lower, while the medians of PC, LA normalized ratio, D-dimer, FDP, FVII, and FVIII were higher. During pregnancy, AT and fPS activity showed a decreasing trend, with the increase of gestational age. PC activity, LA normalized ratio, D-dimer concentrations, FDP concentrations, FVII, and FVIII activity presented an increasing trend, with the increase of gestational age. The non-pregnant women-specific RIs and the gestational age-specific RIs of AT, PC, fPS, LA normalized ratio, D-dimer, FDP, FVII, and FVIII needed to be established for accurate clinical diagnoses.

JTH in Clinic ‐ Obstetric bleeding: VWD and other inherited bleeding disorders

“…Pregnancy provokes changes in most coagulation factors. Fibrinogen, factors V (variable), VII, VIII, X, XI (variable), and VWF increase, while factor XIII decreases 1–9 . Factor IX (FIX) is reported by some to rise and others to not change 8,17,49,50 .…”

“…Fibrinogen, factors V (variable), VII, VIII, X, XI (variable), and VWF increase, while factor XIII decreases. [1][2][3][4][5][6][7][8][9] Factor IX (FIX) is reported by some to rise and others to not change. 8,17,49,50 We have patients where FIX increased with pregnancy.…”

“…In pregnancy, the balance of hemostasis shifts toward a procoagulant state. [1][2][3][4][5][6][7][8][9] These changes are likely adaptive in anticipation of the major hemostatic challenges posed by childbirth. Patients with inherited bleeding disorders (IBDs) have higher bleeding risk during pregnancy, childbirth, and the postpartum period.…”

“…In pregnancy, the balance of hemostasis shifts toward a procoagulant state 1–9 . These changes are likely adaptive in anticipation of the major hemostatic challenges posed by childbirth.…”

Plasma Antithrombin Activity during Long-Term Magnesium Sulfate Administration for Preeclampsia without Severe Hypertension

“…During pregnancy, many coagulation factors (including fibrinogen) are increased, while on the other hand, antithrombin is consumed and its level is decreased [ 10 , 11 ]. These changes result in hypercoagulation states during the antenatal period.…”