Establishment and validation of reference interval of D-dimer in plasma of healthy pregnant women in Xi ′an / 中华检验医学杂志

ABSTRACT

Objective:To provide normal reference thresholds for clinical dynamic monitoring of the risk of microthrombus during pregnancy, we aimed to establish reference intervals of D-dimer in healthy pregnant women during different periods of gestation in Xi′an.Method:From December 2020 to March 2022, a total of 1502 healthy pregnant women and healthy non-pregnant women (healthy non-pregnant control group) who received routine prenatal examination in Northwest Women and Children′s Hospital were recruited in the study by questionnaire, including 1236 healthy pregnant women and 266 healthy non-pregnant control group. Plasma D-dimer concentration was detected by STA-R Evolution automatic blood coagulation analyzer and the concentration levels of D-dimer in different pregnancies and age groups were calculated using Graph Prism 9.0 software. In addition, 20 samples were collected in each pregnancy to verify the established reference interval.Results:There was no significant difference in plasma D-dimer levels between<30 years old and ≥30 years old at different gestational weeks. Plasma D-dimer level in healthy pregnant women group was significantly higher than that in healthy non-pregnant women group of the same age (P<0.05). With the increase of gestational week, plasma D-dimer level in pregnant women increased significantly, and plasma D-dimer level at different gestational weeks ≤13 weeks, 13+ 1-20 weeks, 20+ 1-27 weeks, 27+ 1-35 weeks, ≥35 +1 week were 0.33 (0.26, 0.47) μg/ml, 0.41 (0.30, 0.51) μg/ml, 0.71 (0.48, 0.94) μg/ml, 0.91 (0.70, 1.27) μg/ml, 1.30 (0.96, 1.72) μg/mlrespectively. Unilateral reference interval acuities were≤0.89 μg/ml, ≤1.53 μg/ml, ≤2.44 μg/ml, ≤2.74 μg/ml, ≤3.82 μg/ml respectively. The reference range established in this study was verified by 20 independent samples from each of the 5 gestational age groups, and the results were acceptable. Conclusion:This study preliminarily established the reference interval of plasma D-dimer in healthy pregnant women at different gestational weeks in Xi ′an area, which is helpful for the auxiliary diagnosis of thrombotic diseases during pregnancy.