title: Fraction of cell-free fetal DNA in the maternal serum as a predictor of abnormal placental invasion-a pilot study.
abstract: OBJECTIVE
  Pilot studies have suggested the amount of cell-free fetal DNA (cffDNA) in the maternal serum is increased in pregnancies complicated by placenta accreta. Our objective was to determine if levels of cffDNA can predict invasive placentation.
  
  
  METHODS
  We enrolled women with antenatally suspected placenta accreta compared with gestational age-matched cases of placenta previa and women with prior cesarean deliveries (CDs) and normal placentation. The fetal fraction of cffDNA was quantified using DANSR™ as compared with total DNA. Patient characteristics were compared between the three groups using ANOVA, and linear regression was used to compare the fraction of cffDNA between pathologically confirmed cases of placenta accreta, placenta previa and normal placentation.
  
  
  RESULTS
  Twenty women were enrolled, (seven cases of placenta accreta, six cases of placenta previa and seven cases of normal placentation with prior CD). The groups did not differ by maternal weight, placental weight, number of prior CD or years from prior CD. The mean fraction of cffDNA did not differ significantly by group when controlling for the aforementioned factors (accreta = 19.1%, previa = 27.2%, prior CD = 28.9%, p = 0.26), nor did the median (accreta = 17.0%, previa = 30.1%, prior CD = 22.7%).
  
  
  CONCLUSIONS
  We could not confirm diagnostic benefit. Further investigation of other biomarkers including placental mRNA is warranted.
authors.affiliation: The Divisions of Maternal-Fetal Medicine and Gynecologic Oncology, Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, NY, USA.
authors.forename: Amber
authors.initials: A
authors.lastname: Samuel
authors.forename: Clarissa
authors.initials: C
authors.lastname: Bonanno
authors.forename: Arnold
authors.initials: A
authors.lastname: Oliphant
authors.forename: Annette
authors.initials: A
authors.lastname: Batey
authors.forename: Jason D
authors.initials: JD
authors.lastname: Wright
mesh_terms: D000328:Adult; D002474:Cell-Free System; D004247:DNA / Q000097:blood / Q000378:metabolism*; D005260:Female; D005333:Fetus / Q000378:metabolism*; D005865:Gestational Age; D006801:Humans; D062145:Maternal Serum Screening Tests / Q000379:methods*; D009035:Mothers; D010865:Pilot Projects; D010920:Placenta / Q000002:abnormalities*; D010921:Placenta Accreta / Q000097:blood / Q000175:diagnosis*; D010923:Placenta Previa / Q000097:blood / Q000175:diagnosis; D010929:Placentation; D011247:Pregnancy / Q000097:blood* / Q000378:metabolism; D011379:Prognosis
chemical_list: D004247:DNA