title: Early vaginal bleeding and first-trimester markers for Down syndrome.
abstract: OBJECTIVE
  To assess the effect of early vaginal bleeding on first-trimester markers for Down syndrome.
  
  
  METHODS
  A retrospective study was conducted on 2330 normal singleton fetuses who underwent first-trimester combined screening for Down syndrome based on ultrasound and maternal serum markers. Fetal nuchal translucency (NT), maternal serum pregnancy-associated plasma protein A (PAPP-A), free beta-hCG and the false-positive rate of the test were compared between pregnancies with (n = 253) and without (n = 2077) a history of early vaginal bleeding.
  
  
  RESULTS
  The mean +/- SD log(10) MoM for NT, PAPP-A and free beta-hCG was -0.024 +/- 0.101, 0.007 +/- 0.244, 0.047 +/- 0.273 and -0.011 +/- 0.108, -0.006 +/- 0.223, 0.008 +/- 0.264 in pregnancies with and without a history of early vaginal bleeding, with a p value of 0.07, 0.40 and 0.03 respectively. The false-positive rate was 2.4% and 3.6% (p = 0.33).
  
  
  CONCLUSIONS
  An earlier episode of vaginal bleeding is associated with an increase in maternal serum free beta-hCG levels at first-trimester combined screening for Down syndrome. However, this phenomenon is unlikely to significantly affect the false-positive rate of the test.
authors.affiliation: UO di Ostetricia e Ginecologia, Istituto "G Gaslini", Università di Genova, Italy. bnhdeb@libero.it
authors.forename: Pierangela
authors.initials: P
authors.lastname: De Biasio
authors.forename: Silvana
authors.initials: S
authors.lastname: Canini
authors.forename: Angela
authors.initials: A
authors.lastname: Crovo
authors.forename: Federico
authors.initials: F
authors.lastname: Prefumo
authors.forename: Pier Luigi
authors.initials: PL
authors.lastname: Venturini
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood; D015193:Chorionic Villi Sampling; D004314:Down Syndrome / Q000097:blood / Q000175:diagnosis* / Q000517:prevention & control; D010450:Endopeptidases / Q000097:blood; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008403:Mass Screening / Q000379:methods; D008423:Maternal Age; D008875:Middle Aged; D009333:Neck / Q000002:abnormalities / Q000000981:diagnostic imaging; D011247:Pregnancy / Q000097:blood; D011257:Pregnancy Proteins / Q000097:blood; D011261:Pregnancy Trimester, First; D018566:Pregnancy, High-Risk; D011266:Pregnancy-Associated Plasma Protein-A; D011296:Prenatal Diagnosis / Q000379:methods*; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal; D014592:Uterine Hemorrhage / Q000097:blood
chemical_list: D015415:Biomarkers; D018997:Chorionic Gonadotropin, beta Subunit, Human; D011257:Pregnancy Proteins; D010450:Endopeptidases; C430889:PAPPA2 protein, human; D011266:Pregnancy-Associated Plasma Protein-A