D-Dimer levels at different stages of pregnancy in Australian women: A single centre study using two different immunoturbidimetric assays

• Published in: Thrombosis research Vol. 130; no. 3; pp. e171 - e177
• Main Authors: Khalafallah, Alhossain A., Morse, Michael, Al-Barzan, Abdul-Majeed, Adams, Murray, Dennis, Amanda, Bates, Gerald, Robertson, Iain, Seaton, David, Brain, Terry
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.09.2012
• Subjects: Adolescent; Adult; Australia - epidemiology; Blood Chemical Analysis - statistics & numerical data; D-Dimer PLUS; Female; Fibrin Fibrinogen Degradation Products - analysis; Hematology, Oncology and Palliative Medicine; Humans; Immunoassay - methods; Immunoassay - statistics & numerical data; INNOVANCE D-Dimer; Nephelometry and Turbidimetry - methods; Nephelometry and Turbidimetry - statistics & numerical data; Outcome; Pregnancy; Pregnancy Complications, Cardiovascular - blood; Pregnancy Complications, Cardiovascular - epidemiology; Pregnancy Trimesters; Prevalence; Reproducibility of Results; Sensitivity and Specificity; Young Adult; Australia; Pregnancy; D-Dimer PLUS; Outcome; INNOVANCE D-Dimer
• ISSN: 0049-3848; 1879-2472; 1879-2472
• DOI: 10.1016/j.thromres.2012.05.022

To date there is minimal data available on D-Dimer levels at different stages of pregnancy. We prospectively measured D-Dimer levels in 632 consecutive pregnant women from March 2007 to January 2009. The median age of the participants was 31years (range; 18–42) with a median weight of 78 kilograms (range; 46–137). All subjects were investigated during each trimester with two different immunoturbidimetric assays; D-Dimer PLUS and INNOVANCE D-Dimer. D-Dimer levels were determined using a Sysmex® CA 1500 analyser. Our data demonstrate that D-Dimer levels in pregnancy show different patterns of rise within the first trimester, depending on the assay used; D-Dimer PLUS=0.88 (SD: mean ratio), INNOVANCE D-Dimer=0.72 (SD: mean ratio). Furthermore, the rise in mean results was greater for the INNOVANCE D-Dimer assay compared to the D-Dimer PLUS assay as shown by the ratio of third to first trimester results of 3.68 and 1.96 respectively. Both D-Dimer assays demonstrated moderate levels of intra-subject variability, with overall mean CVs of 16.5% (D-Dimer PLUS) and 16.9% (INNOVANCE D-Dimer). Furthermore, we studied the association between D-Dimer levels and occurrence of diseases of pregnancy. For both assays, there was no consistently interpretable evidence of an association between raised mean D-Dimer levels or rising D-Dimer levels and any of the diseases or conditions associated with pregnancy. Our data suggest that the INNOVANCE D-Dimer assay increases significantly with the advancement of pregnancy, and is more sensitive than D-Dimer PLUS assay in the pregnant population.