Home Medicine Within-subject biological variation of activated partial thromboplastin time, prothrombin time, fibrinogen, factor VIII and von Willebrand factor in pregnant women
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Within-subject biological variation of activated partial thromboplastin time, prothrombin time, fibrinogen, factor VIII and von Willebrand factor in pregnant women

  • Ann Helen Kristoffersen EMAIL logo , Per Hyltoft Petersen , Line Bjørge , Thomas Røraas and Sverre Sandberg
Published/Copyright: April 12, 2018
Clinical Chemistry and Laboratory Medicine (CCLM)
From the journal Clinical Chemistry and Laboratory Medicine (CCLM) Volume 56 Issue 8

Abstract

Background:

During pregnancy, interpretation of results from coagulation parameters can be difficult as the physiological changes that occur may affect the biochemical parameters. The aim of this study was to describe the normal course of five coagulation parameters in healthy pregnancies, and to estimate the within-subject biological variation (CVI).

Methods:

Blood samples were obtained every 4th week during pregnancy and three samples after delivery in 20 healthy women and every 4th week during a 40-week period in 19 healthy non-pregnant women. Activated partial thromboplastin time (APTT), prothrombin time (PT), PT International Normalized Ratio (INR), fibrinogen, factor VIII clot (FVIII:C) and von Willebrand factor antigen (vWF:Ag) were analyzed. The physiological changes during pregnancy were compensated by transformation into multiples of the median (MoM) and it is natural logarithm (lnMoM) in order to establish a kind of steady state, and CVI was calculated from the standard deviation.

Results:

During pregnancy, APTT, PT and INR remained unchanged or decreased, depending upon the reagent used, while fibrinogen, FVIII:C and vWF:Ag increased gradually until delivery. The CVI in pregnancy were 2.2 and 3.0% for APTT, 2.3 and 2.6% for PT, 2.2 and 2.3% for INR, 7.2% for fibrinogen, 12.2% for FVIII:C and 11.3% for vWF:Ag, and corresponded with the CVI in non-pregnant women.

Conclusions:

Transformation of coagulation parameters in healthy pregnancies to MoM is a tool to establish a kind of steady state. Although there is a physiological change in these coagulation parameters during pregnancy, the CVI after lnMoM transformation was comparable with the CVI of non-pregnant women.

Keywords: biological variation; blood coagulation tests; haemostasis; multiples of median; pregnancy
Corresponding author: Ann Helen Kristoffersen, MD, PhD, Laboratory of Clinical Biochemistry, Helse Bergen HF, Haukeland University Hospital, PB 1400, 5021 Bergen, Norway, Phone: +47 55973113, and Norwegian Quality Improvement of Laboratory Examinations (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway

Acknowledgments

We would like to thank Bente Asbjørnsen and Solveig Vannes for excellent technical assistance. Thanks also to STAGO for supporting the study with reagents free of cost and Axis-Shield for Cephotest reagents free of costs. Additional appreciations to the Western Norway Regional Health Authority for supporting AH Kristoffersen with PhD and a postdoctoral fellowship, Funder Id: 10.13039/501100004257.

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: Declared (see Acknowledgments)

  3. Employment or leadership: None declared.

  4. Honorarium: None declared.

  5. Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.

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Supplementary Material:

The online version of this article offers supplementary material (https://doi.org/10.1515/cclm-2017-1220).

Received: 2017-12-29
Accepted: 2018-02-13
Published Online: 2018-04-12
Published in Print: 2018-07-26

©2018 Walter de Gruyter GmbH, Berlin/Boston

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https://doi.org/10.1515/cclm-2017-1220
Keywords for this article
biological variation; blood coagulation tests; haemostasis; multiples of median; pregnancy

Articles in the same Issue

  1. Frontmatter
  2. Editorials
  3. Procalcitonin for diagnosing and monitoring bacterial infections: for or against?
  4. Is it time to abandon the Nobel Prize?
  5. In Memoriam
  6. Norbert Tietz, 13th November 1926–23rd May 2018
  7. Reviews
  8. Procalcitonin guidance in patients with lower respiratory tract infections: a systematic review and meta-analysis
  9. Telomere biology and age-related diseases
  10. Opinion Paper
  11. Procalcitonin-guided antibiotic therapy: an expert consensus
  12. Genetics and Molecular Diagnostics
  13. mRNA expression profile in peripheral blood mononuclear cells based on ADRB1 Ser49Gly and Arg389Gly polymorphisms in essential hypertension — a case-control pilot investigation in South Indian population
  14. General Clinical Chemistry and Laboratory Medicine
  15. External quality assessment schemes for glucose measurements in Germany: factors for successful participation, analytical performance and medical impact
  16. Long-term stability of glucose: glycolysis inhibitor vs. gel barrier tubes
  17. Observational studies on macroprolactin in a routine clinical laboratory
  18. Anti-streptavidin IgG antibody interference in anti-cyclic citrullinated peptide (CCP) IgG antibody assays is a rare but important cause of false-positive anti-CCP results
  19. Point-of-care creatinine testing for kidney function measurement prior to contrast-enhanced diagnostic imaging: evaluation of the performance of three systems for clinical utility
  20. Hematology and Coagulation
  21. Analytical performance of an automated volumetric flow cytometer for quantitation of T, B and natural killer lymphocytes
  22. Lupus anticoagulant testing using two parallel methods detects additional cases and predicts persistent positivity
  23. Reference Values and Biological Variations
  24. Within-subject biological variation of activated partial thromboplastin time, prothrombin time, fibrinogen, factor VIII and von Willebrand factor in pregnant women
  25. Within-subject and between-subject biological variation estimates of 21 hematological parameters in 30 healthy subjects
  26. Immunoglobulin G (IgG) and IgG subclass reference intervals in children, using Optilite® reagents
  27. Cancer Diagnostics
  28. Serum carbohydrate sulfotransferase 7 in lung cancer and non-malignant pulmonary inflammations
  29. Cardiovascular Diseases
  30. Clinical performance of a new point-of-care cardiac troponin I test
  31. Diabetes
  32. Testing for HbA1c, in addition to the oral glucose tolerance test, in screening for abnormal glucose regulation helps to reveal patients with early β-cell function impairment
  33. Effects of common hemoglobin variants on HbA1c measurements in China: results for α- and β-globin variants measured by six methods
  34. Infectious Diseases
  35. Serum procalcitonin concentration within 2 days postoperatively accurately predicts outcome after liver resection
  36. Predictive value of serum gelsolin and Gc globulin in sepsis – a pilot study
  37. Cerebrospinal fluid free light chains as diagnostic biomarker in neuroborreliosis
  38. Letter to the Editor
  39. Glucose and total protein: unacceptable interference on Jaffe creatinine assays in patients
  40. Interference of glucose and total protein on Jaffe-based creatinine methods: mind the covolume
  41. Interference of glucose and total protein on Jaffe based creatinine methods: mind the covolume – reply
  42. Measuring procalcitonin to overcome heterophilic-antibody-induced spurious hypercalcitoninemia
  43. Paraprotein interference in the diagnosis of hepatitis C infection
  44. Timeo apis mellifera and dona ferens: bee sting-induced Kounis syndrome
  45. Bacterial contamination of reusable venipuncture tourniquets in tertiary-care hospital
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  47. Early adjustment of antimicrobial therapy after PCR/electrospray ionization mass spectrometry-based pathogen detection in critically ill patients with suspected sepsis
  48. Thromboelastometry reveals similar hemostatic properties of purified fibrinogen and a mixture of purified cryoprecipitate protein components
  49. Bicarbonate interference on cobas 6000 c501 chloride ion-selective electrodes
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