摘要目的:探讨孕产妇孕期及产后2 d内血浆D-二聚体水平的变化趋势和参考范围，分析孕产妇血浆D-二聚体水平升高的影响因素和临床诊断价值。方法:本研究为回顾性病例对照研究。收集2020年1月1日至2024年7月31日于广州医科大学附属第三医院门诊及住院的10 129例孕产妇临床资料，年龄（32.86±4.92）岁。其中孕早期974例，孕中期1 924例，孕晚期6 595例，产后2 d内636例。根据孕产妇有无发生静脉血栓栓塞症（VTE）分为无VTE组（9 854例）和VTE组（275例），再根据妊娠相关危险因素（高血压/非高血压、糖尿病/非糖尿病、单胎/多胎、自然受孕/辅助生殖受孕）、生产方式（剖宫产/阴道分娩）及孕周（孕早期：孕周＜13周；孕中期：13周≤孕周＜28周；孕晚期：28周≤孕周＜42周；产后2 d内）进行亚组分析。比较无VTE组和VTE组间血浆D-二聚体水平的差异，建立血浆D-二聚体水平的95%参考区间的单侧上限。采用二元Logistic回归分析孕产妇血浆D-二聚体水平与VTE发生风险的相关性。采用受试者工作特征曲线评价血浆D-二聚体水平对VTE的诊断效果。结果:无VTE组孕产妇血浆D-二聚体的95%单侧参考范围：孕早期≤401.80 ng/ml、孕中期≤2 221.10 ng/ml、孕晚期≤3 012.50 ng/ml、产后2 d内≤8 967.30 ng/ml。9 854例无VTE孕产妇中，高血压组较非高血压组、糖尿病组较非糖尿病组、多胎组较单胎组、辅助生殖组较自然受孕组血浆D-二聚体水平均更高，差异均有统计学意义（均 P＜0.05）；剖宫产组与阴道分娩组血浆D-二聚体水平差异无统计学意义（ P=0.930）。Logistic回归分析显示，孕早期和孕晚期孕妇血浆D-二聚体水平升高与VTE风险增加有关（孕早期： OR=1.436，95% CI：1.313~1.570， P＜0.001；孕晚期： OR=1.007，95% CI：1.004~1.011， P＜0.001）；孕中期和产后2 d内血浆D-二聚体水平与VTE风险无相关性（均 P＞0.05）。孕早期血浆D-二聚体排除VTE的最佳截断值为515.00 ng/ml，敏感性为93.3%，特异性为96.8%，曲线下面积（AUC）为0.983；孕中期血浆D-二聚体排除VTE的最佳截断值为515.50 ng/ml，敏感性为84.6%，特异性为67.1%，AUC为0.801；孕晚期血浆D-二聚体排除VTE的最佳截断值为684.50 ng/ml，敏感性为82.7%，特异性为58.9%，AUC为0.757。VTE孕产妇产后2 d内血浆D-二聚体水平与非VTE孕产妇比较，差异无统计学意义（ U=18 559.500， P=0.859）。 结论:无VTE孕产妇孕中期、孕晚期及产后2 d内D-二聚体水平高于未怀孕妇女，且随着孕周的增加，血浆D-二聚体水平也逐步升高。高血压、糖尿病、多胎妊娠、辅助生殖受孕可能使孕产妇血浆D-二聚体水平进一步升高。血浆D-二聚体在妊娠期有助于排除孕产妇VTE诊断，特别是在孕早期，但随着孕周的增加，诊断价值也随之下降，到产后2 d内血浆D-二聚体不具备临床诊断价值。

abstractsObjective:To explore the change characteristics and the reference range of plasma D-dimer levels during pregnant and puerperal women, as well as their influencing factors and clinical diagnostic value.Methods:This retrospective case-control study included clinical data from 11,967 pregnant women who visited the Third Affiliated Hospital of Guangzhou Medical University between January 1, 2020, and July 31, 2024. After exclusions, 10,129 pregnant women [mean age (32.86±4.92) years] were enrolled. Participants were divided into a non-VTE group (9,854 cases) and a VTE group (275 cases) based on whether they developed venous thromboembolism (VTE). Subgroup analyses were conducted according to pregnancy-related risk factors (hypertension/non-hypertension, diabetes/non-diabetes, singleton/multiple pregnancies, natural conception/assisted reproductive technology), mode of delivery (cesarean section/vaginal delivery), and gestational age (early pregnancy: gestational age <13 weeks; mid-pregnancy: 13 ≤ gestational age <28 weeks; late pregnancy: 28 ≤ gestational age <42 weeks; postpartum within 2 days). Plasma D-dimer levels were compared between the non-VTE and VTE groups, and the upper unidirectional limit of the 95% reference interval for plasma D-dimer levels was established. Binary logistic regression was used to analyze the correlation between plasma D-dimer levels and VTE risk in pregnant women. The diagnostic performance of plasma D-dimer for VTE was evaluated using the receiver operating characteristic curve.Results:The 95% upper reference limits for plasma D-dimer levels in the non-VTE group were as follows: ≤401.80 ng/ml in early pregnancy, ≤2,221.10 ng/ml in mid-pregnancy, ≤3,012.50 ng/ml in late pregnancy, and ≤8,967.30 ng/ml within 2 days postpartum. Plasma D-dimer levels were significantly higher in the hypertension group compared to the non-hypertension group, in the diabetes group compared to the non-diabetes group, in the multiple pregnancy group compared to the singleton group, and in the assisted reproductive technology group compared to the natural conception group (all P < 0.05). No significant difference in plasma D-dimer levels was observed between the cesarean section and vaginal delivery groups ( P = 0.930). Logistic regression analysis showed that elevated plasma D-dimer levels in early and late pregnancy were associated with an increased risk of VTE (early pregnancy: OR = 1.436, 95% CI: 1.313~1.570, P < 0.001; late pregnancy: OR = 1.007, 95% CI: 1.004~1.011, P < 0.001). No significant correlation was found between plasma D-dimer levels in mid-pregnancy and postpartum within 2 days and VTE risk (all P > 0.05). The optimal cutoff value for plasma D-dimer to exclude VTE in early pregnancy was 515.00 ng/ml, with a sensitivity of 93.3%, specificity of 96.8%, and area under the curve (AUC) of 0.983. In mid-pregnancy, the optimal cutoff value was 515.50 ng/ml, with a sensitivity of 84.6%, specificity of 67.1%, and AUC of 0.801. In late pregnancy, the optimal cutoff value was 684.50 ng/ml, with a sensitivity of 82.7%, specificity of 58.9%, and AUC of 0.757. No significant difference in plasma D-dimer levels within 2 days postpartum was observed between VTE and non-VTE groups ( U = 18,559.500, P = 0.859). Conclusion:Plasma D-dimer levels in non-VTE pregnant women during mid-pregnancy, late pregnancy, and within 2 days postpartum are higher than in non-pregnant women, and increase progressively with advancing gestational age. Hypertension, diabetes, multiple pregnancies, and assisted reproductive technology may further elevate plasma D-dimer levels in pregnant women. Plasma D-dimer levels during pregnancy may assist in excluding VTE in pregnant women, particularly in early pregnancy; however, diagnostic value decreases with advancing gestational age and is absent within 2 days postpartum.