title: Pregnancy-associated plasma protein A and alpha-fetoprotein and prediction of adverse perinatal outcome.
abstract: OBJECTIVE
  To describe the association between pregnancy associated plasma protein A (PAPP-A), alpha-fetoprotein (AFP) and adverse perinatal outcome.
  
  
  METHODS
  We conducted a multicenter prospective cohort study of 8,483 women attending for prenatal care in southern Scotland between 1998 and 2000. The risk of delivering a small for gestational age infant, delivering preterm, and stillbirth were related to maternal serum levels of PAPP-A and AFP.
  
  
  RESULTS
  Women with a low PAPP-A were not more likely to have elevated levels of AFP. Compared with women with a normal PAPP-A and a normal AFP, the odds ratio for delivering a small for gestational age infant for women with a high AFP was 0.9 (95% confidence interval [CI] 0.5-1.6), for women with a low PAPP-A was 2.8 (95% CI 2.0-4.0), and for women with both a high AFP and a low PAPP-A was 8.5 (95% CI 3.6-20.0). The odds ratio for delivering preterm for women with a high AFP was 1.8 (95% CI 1.3-2.7), for women with a low PAPP-A was 1.9 (95% CI 1.3-2.7), and for women with both a low PAPP-A and a high AFP was 9.9 (95% CI 4.4-22.0). These interactions were statistically significant for both outcomes (P = .03 and .04, respectively). There was a nonsignificant trend toward a similar interaction in relation to stillbirth risk. Of the women with the combination of a low PAPP-A and high AFP, 32.1% (95% CI 15.9-52.4) delivered a low birth weight infant.
  
  
  CONCLUSIONS
  Low maternal serum levels of PAPP-A between 10 and 14 weeks and high levels of AFP between 15 and 21 weeks gestation are synergistically associated with adverse perinatal outcome.
  
  
  METHODS
  II-2.
authors.affiliation: Department of Obstetrics and Gynaecology, Cambridge University, Cambridge, United Kingdom. gcss2@cam.ac.uk
authors.forename: Gordon C S
authors.initials: GC
authors.lastname: Smith
authors.forename: Imran
authors.initials: I
authors.lastname: Shah
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Crossley
authors.forename: David A
authors.initials: DA
authors.lastname: Aitken
authors.forename: Jill P
authors.initials: JP
authors.lastname: Pell
authors.forename: Scott M
authors.initials: SM
authors.lastname: Nelson
authors.forename: Alan D
authors.initials: AD
authors.lastname: Cameron
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Connor
authors.forename: Richard
authors.initials: R
authors.lastname: Dobbie
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007236:Infant, Small for Gestational Age; D008297:Male; D008423:Maternal Age; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D011266:Pregnancy-Associated Plasma Protein-A / Q000378:metabolism*; D011295:Prenatal Care / Q000379:methods; D011296:Prenatal Diagnosis / Q000379:methods*; D011336:Probability; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D050497:Stillbirth; D006113:United Kingdom
chemical_list: D015415:Biomarkers; D011266:Pregnancy-Associated Plasma Protein-A