title: Fibrinogen levels in the late stage of twin pregnancy.
abstract: BACKGROUND
  Twin pregnancy is a risk factor of complications, such as pregnancy-induced hypertension, venous thromboembolism, and postpartum hemorrhage, the pathogenesis of which may involve aberrations of the coagulation-fibrinolysis system.
  
  
  METHODS
  Fibrinogen data for 129 and 1202 blood specimens from 84 and 902 women with twin and singleton pregnancies, respectively, at gestational week (GW)≥32 were analyzed retrospectively. None of the 986 women developed complications in which blood fibrinogen levels may be altered. Thirty-six and 288 women with twin and singleton pregnancies were examined longitudinally, respectively.
  
  
  RESULTS
  The fibrinogen levels of 403±63 and 403±77 mg/dL at GW 32-33 and 34-35, respectively, decreased significantly to 366±57 mg/dL at GW 36-37 in women with twins, while corresponding levels (422±79, 420±65, and 415±64, respectively) and that at GW≥38 (408±60 mg/dL) did not change significantly in women with singleton pregnancies. The fibrinogen levels determined within 3 weeks before delivery were consistently and significantly lower in women with twin than singleton pregnancies. The fibrinogen levels were significantly inversely correlated with GW in women with twins (R=-0.36, P=0.002), but not in those with singleton pregnancies.
  
  
  CONCLUSIONS
  The fibrinogen level of twin pregnancy decreases significantly and is significantly lower than that in singleton pregnancy in the last few weeks of pregnancy.
authors.affiliation: Department of Obstetrics, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan. Electronic address: yamatakashi@me.com.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamada
authors.affiliation: Department of Obstetrics, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Morikawa
authors.affiliation: Department of Obstetrics, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Yamada
authors.affiliation: Department of Obstetrics, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
authors.forename: Rina
authors.initials: R
authors.lastname: Akaishi
authors.affiliation: Department of Obstetrics, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kojima
authors.affiliation: Department of Obstetrics, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
authors.forename: Hisanori
authors.initials: H
authors.lastname: Minakami
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D005340:Fibrinogen / Q000032:analysis / Q000378:metabolism*; D006801:Humans; D011247:Pregnancy; D059285:Pregnancy, Twin / Q000097:blood*; D012189:Retrospective Studies
chemical_list: D005340:Fibrinogen
keywords: Coagulation–fibrinolysis; Fibrinogen; Postpartum hemorrhage; Twin pregnancy; Venous thromboembolism