title: Significant correlation between maternal body mass index at delivery and in the second trimester, and second trimester circulating total cell-free DNA levels.
abstract: OBJECTIVE
  The use of cell-free fetal deoxyribonucleic acid (DNA) requires the knowledge of variables that may influence the levels of cell-free DNA, such as maternal body mass index (BMI).
  
  
  METHODS
  In this study, using 406 maternal blood samples from the second trimester of pregnancy, cell-free fetal DNA specific for the SRY and DYS14 loci and glyceraldehyde-3-phosphate dehydrogenase sequence were quantified by real-time polymerase chain reaction.
  
  
  RESULTS
  No significant correlation was seen between the levels of cell-free fetal DNA and maternal BMI, whereas total cell-free DNA was significantly associated with maternal BMI at 20 to 21 weeks of gestation (P = .034) and at the end of pregnancy (R2 regression: 0.016, P = .014).
  
  
  CONCLUSIONS
  Quantitative levels of cell-free fetal DNA are not affected by maternal BMI, whereas total DNA levels in the second trimester significantly correlate with maternal BMI at the moment of blood drawing and at delivery.
authors.affiliation: Department of Obstetrics and Gynecology, University of Basel, Basel, Switzerland.
authors.forename: Olav
authors.initials: O
authors.lastname: Lapaire
authors.forename: Thorsten
authors.initials: T
authors.lastname: Volgmann
authors.forename: Simon
authors.initials: S
authors.lastname: Grill
authors.forename: Irène
authors.initials: I
authors.lastname: Hösli
authors.forename: Rosanna
authors.initials: R
authors.lastname: Zanetti-Daellenbach
authors.forename: Xiao Yan
authors.initials: XY
authors.lastname: Zhong
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Holzgreve
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001724:Birth Weight; D015992:Body Mass Index; D004247:DNA / Q000097:blood*; D005260:Female; D005333:Fetus / Q000378:metabolism*; D005858:Germany; D005865:Gestational Age; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008431:Maternal-Fetal Exchange; D036801:Parturition; D010920:Placenta / Q000098:blood supply; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011262:Pregnancy Trimester, Second / Q000097:blood; D011446:Prospective Studies; D015203:Reproducibility of Results; D012732:Sex Determination Analysis; D051876:Sex-Determining Region Y Protein / Q000235:genetics; D013557:Switzerland; D055815:Young Adult
chemical_list: D015415:Biomarkers; C497745:SRY protein, human; D051876:Sex-Determining Region Y Protein; D004247:DNA; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases