title: Reference Intervals of Routine Coagulation Assays During the Pregnancy and Puerperium Period.
abstract: BACKGROUND
  Significant changes occur in the coagulation and fibrinolytic systems during pregnancy and puerperium in the plasma levels. However, reference ranges based on healthy people are not optimal for informing clinical decisions during the pregnancy and puerperium. Therefore, it is essential to explore coagulation assays' reference ranges during the pregnancy and puerperium.
  
  
  METHODS
  Prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (Fib.), and D-dimer were all measured according to the manufacturer's specifications and laboratory standard operating procedure of the STA-R evolution coagulation analyzer. A total of 11,601 women were enrolled in this study.
  
  
  RESULTS
  The reference ranges for PT, APTT, TT, Fib., and D-dimer in nonpregnancy period were 10.87-13.76 s, 29.22-44.61 s, 15.39-20.15 s, 1.59-3.97 g/l, and 0-0.56 mg/l, respectively. In early-pregnancy period, the ranges were 11.14-14.07 s, 29.97-44.69 s, 14.92-19.03 s, 1.98-4.13 g/l, and 0-1.67 mg/l, respectively. In midpregnancy period, the ranges were 9.98-12.84 s, 28.53-40.70 s, 13.51-19.82 s, 2.63-5.19 g/l, and 0-2.81 mg/l, respectively. In late-pregnancy period, the ranges were 9.48-12.58 s, 28.61-40.80 s, 14.10-19.61 s, 2.80-5.56 g/l, and 0-27.08 mg/l, respectively. In puerperium period, the ranges were 10.85-13.72 s, 30.51-43.02 s, 15.31-19.64 s, 1.14-5.07 g/l, and 1.27-4.85 mg/l, respectively.
  
  
  CONCLUSIONS
  We presented reference intervals for coagulation assays from the nonpregnancy to puerperium period that can be adopted in other laboratories after further validation.
authors.affiliation: Department of Clinical Laboratory, the Second Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Jiao-Mei
authors.initials: JM
authors.lastname: Gong
authors.affiliation: Department of Clinical Laboratory, Affiliated Tumor Hospital of Zhengzhou University, Henan Tumor Hospital, Zhengzhou, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Department of Clinical Laboratory, the Second Affiliated Hospital of Zhengzhou University, Zhengzhou, China. heyanxiamy@126.com.
authors.forename: Yan-Xia
authors.initials: YX
authors.lastname: He
mesh_terms: D000293:Adolescent; D000328:Adult; D000465:Algorithms; D001777:Blood Coagulation / Q000502:physiology*; D001780:Blood Coagulation Tests / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D008875:Middle Aged; D049590:Postpartum Period / Q000502:physiology*; D011247:Pregnancy / Q000502:physiology*; D011517:Prothrombin Time; D012016:Reference Values; D055815:Young Adult
keywords: STA-R; coagulation assays; pregnancy; puerperium; reference intervals