title: Vaginal bleeding in early pregnancy and circulating markers of thrombin generation.
abstract: OBJECTIVE
  To determine if subjects experiencing acute vaginal bleeding in early pregnancy have increased plasma markers of thrombin generation compared to nonbleeding controls.
  
  
  METHODS
  Subjects with clinically apparent acute (within 24 h of sample collection) vaginal bleeding between 6 and 20 weeks estimated gestational age and without known thrombophilias were enrolled, along with nonbleeding controls, and underwent collection of maternal plasma. Concentrations of thrombin-antithrombin (TAT) and fragment 1 + 2 (F1 + 2) were determined by enzyme-linked immunosorbent assay. Differences between bleeding and nonbleeding subjects were assessed through linear regression with adjustment for gestational age.
  
  
  RESULTS
  Twenty subjects with vaginal bleeding and 20 controls were included. Bleeding was significantly associated with increased concentrations of TAT (p = 0.007) and F1 + 2 (p = 0.044) when corrected for gestational age. Among bleeding subjects, there was no association between markers of thrombin generation and the subject's description of bleeding quantity, though higher concentrations were associated with a longer self-reported duration of bleeding.
  
  
  CONCLUSIONS
  Clinically apparent vaginal bleeding in early pregnancy is associated with increased circulating maternal markers of thrombin generation. Thus, these maternal markers may have a future role in risk stratification.
authors: Department of Obstetrics and Gynecology, University of Rochester School of Medicine, Rochester, NY 14642, USA. david_hackney@URMC.rochester.edu
authors: David N
authors: DN
authors: Hackney
authors: Richard K
authors: RK
authors: Miller
authors: Eva K
authors: EK
authors: Pressman
authors: Charles W
authors: CW
authors: Francis
authors: Hyagriv N
authors: HN
authors: Simhan
mesh_terms: D000293:Adolescent; D000328:Adult; D000991:Antithrombins / Q000032:analysis / Q000097:blood; D015415:Biomarkers / Q000032:analysis / Q000097:blood*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000097:blood* / Q000502:physiology; D011516:Prothrombin / Q000032:analysis; D013917:Thrombin / Q000096:biosynthesis*; D014592:Uterine Hemorrhage / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism; D055815:Young Adult
chemical_list: D000991:Antithrombins; D015415:Biomarkers; D011516:Prothrombin; D013917:Thrombin