title: First trimester maternal serum ADAM12s levels in twin pregnancies.
abstract: BACKGROUND
  A disintegrin and metalloprotease 12s (ADAM12s) is a potential first trimester serum marker for fetal trisomy and adverse pregnancy outcome in singletons. In this study, ADAM12s levels in first trimester serum of uncomplicated and complicated twins were evaluated.
  
  
  METHODS
  ADAM12s was studied in maternal serum of 215 twin pregnancies, collected between 2004 and 2008. ADAM12s was measured 'blind to outcome' using AutoDelfia (PerkinElmer, Turku, Finland). As a reference, data from 2423 singletons were used.
  
  
  RESULTS
  The median ADAM12s level was increased in euploid twins [1.61 multiples of the median (MoM); n = 209] compared with singletons. The median ADAM12s MoM was significantly lower in monochorionic (1.36 MoM; n = 41) compared with dichorionic twins (1.67 MoM; n = 168) (Mann-Whitney U test, p = 0.005). Trisomy 21 was identified in two pregnancies. Median ADAM12s MoM in twins complicated by hypertensive disorders (1.77 MoM, n = 35) or small for gestational age fetus (1.54 MoM; n = 24) was not significantly different from uncomplicated twins (1.64 MoM; n = 134).
  
  
  CONCLUSIONS
  Median ADAM12s MoM in euploid twins was increased compared with singletons. Monochorionic had significantly lower median ADAM12s MoM than dichorionic twins. Median ADAM12s MoMs were not significantly different in twins complicated by hypertensive disorders or small for gestational age fetus compared with uncomplicated twins.
authors.affiliation: Department of Obstetrics and Gynecology, VU University Medical Center, Amsterdam, The Netherlands. I.Linskens@vumc.nl
authors.forename: I H
authors.initials: IH
authors.lastname: Linskens
authors.forename: J W R
authors.initials: JW
authors.lastname: Twisk
authors.forename: M A
authors.initials: MA
authors.lastname: Blankenstein
authors.forename: J M G
authors.initials: JM
authors.lastname: van Vugt
mesh_terms: D051722:ADAM Proteins / Q000097:blood*; D000072199:ADAM12 Protein; D000328:Adult; D005260:Female; D006801:Humans; D008565:Membrane Proteins / Q000097:blood*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood; D011261:Pregnancy Trimester, First / Q000097:blood; D014427:Twins / Q000097:blood*; D055815:Young Adult
chemical_list: D008565:Membrane Proteins; D051722:ADAM Proteins; D000072199:ADAM12 Protein; C000606480:ADAM12 protein, human