title: Circulating matrix metalloproteinase MMP-9 and MMP-2/TIMP-2 complex are associated with spontaneous early pregnancy failure.
abstract: BACKGROUND
  Trophoblast cell (CTB) invasion into the maternal endometrium plays a crucial role during human embryo implantation and placentation. This invasion is facilitated by the activity of matrix metalloproteinases, which are regulated by tissue inhibitors of MMPs (TIMPs).
  
  
  METHODS
  This study compares the serum levels of MMP-9, MMP-2/TIMP-2 complex, TIMP-1 and TIMP-2 in 129 patients with ongoing pregnancy (n = 40) or spontaneous early pregnancy failure (n = 89).
  
  
  RESULTS
  MMP-9 was markedly (p < 0.0001) elevated in missed abortions, as was MMP-2/TIMP-2 complex (p < 0.0005). However, the serum levels of TIMP-1 and TIMP-2 were markedly elevated (p < 0.0001) in ongoing pregnancies.
  
  
  CONCLUSIONS
  Human placentation is mediated by fetal trophoblastic cells that invade the maternal uterine endometrium. Trophoblast invasion requires a precisely regulated secretion of specific proteolytic enzymes able to degrade the endometrial basement membrane and extracellular matrix. The elevated levels of MMP-9 and MMP-2/TIMP-2 complex may play a role in spontaneous termination of pregnancy.
authors: Department of Obstetrics and Gynecology, Oulu University Hospital, Kajaanintie 52A, Oulu, 90220, Finland. ritva.nissi@oulu.fi
authors: Ritva
authors: R
authors: Nissi
authors: Anne
authors: A
authors: Talvensaari-Mattila
authors: Vesa
authors: V
authors: Kotila
authors: Maarit
authors: M
authors: Niinimäki
authors: Ilkka
authors: I
authors: Järvelä
authors: Taina
authors: T
authors: Turpeenniemi-Hujanen
mesh_terms: D000030:Abortion, Missed / Q000201:enzymology; D000022:Abortion, Spontaneous / Q000201:enzymology*; D000328:Adult; D005260:Female; D005865:Gestational Age; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000097:blood*; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D010929:Placentation / Q000502:physiology; D011247:Pregnancy; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000097:blood*; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000097:blood*; D014327:Trophoblasts / Q000502:physiology
chemical_list: C560822:TIMP1 protein, human; C560823:TIMP2 protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9