title: Prediction of small-for-gestational-age neonates: screening by maternal biochemical markers at 30-34 weeks.
abstract: OBJECTIVE
  To investigate the potential value of serum placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1), pregnancy-associated plasma protein-A (PAPP-A), free β-human chorionic gonadotropin (β-hCG) and α-fetoprotein (AFP) at 30-34 weeks' gestation in the prediction of delivery of small-for-gestational-age (SGA) neonates, in the absence of pre-eclampsia (PE).
  
  
  METHODS
  This was a screening study in singleton pregnancies at 30-34 weeks' gestation, including 490 that delivered SGA neonates and 9360 cases that were unaffected by SGA, PE or gestational hypertension (normal outcome). Multivariable logistic regression analysis was used to determine if screening by serum PlGF, sFlt-1, PAPP-A, free β-hCG and AFP, individually or in combination, improved the prediction of SGA neonates provided by screening with maternal characteristics and medical history (maternal factors), and estimated fetal weight (EFW) from fetal head circumference, abdominal circumference and femur length.
  
  
  RESULTS
  Compared to the normal group, the mean log10 multiples of the median (MoM) values of PlGF and AFP were significantly lower and the mean log10 MoM values of sFlt-1 and free β-hCG were significantly higher in the SGA group with a birth weight < 5(th) percentile (SGA < 5(th)) delivering < 5 weeks following assessment. The best model for prediction of SGA was provided by a combination of maternal factors, EFW and serum PlGF. Such combined screening, predicted, at a 10% false-positive rate, 85%, 93% and 92% of SGA neonates delivering < 5 weeks following assessment with birth weight < 10(th), < 5(th) and < 3(rd) percentiles, respectively; the respective detection rates of combined screening for SGA neonates delivering ≥ 5 weeks following assessment were 57%, 64% and 71%.
  
  
  CONCLUSIONS
  Combined screening by maternal factors, EFW and serum PlGF at 30-34 weeks' gestation can identify a high proportion of pregnancies that subsequently deliver SGA neonates.
authors.affiliation: Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Bakalis
authors.affiliation: Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London, UK.
authors.forename: D M
authors.initials: DM
authors.lastname: Gallo
authors.affiliation: Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London, UK.
authors.forename: O
authors.initials: O
authors.lastname: Mendez
authors.affiliation: Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London, UK.
authors.forename: L C
authors.initials: LC
authors.lastname: Poon
authors.affiliation: Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London, UK.
authors.forename: K H
authors.initials: KH
authors.lastname: Nicolaides
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000378:metabolism*; D005260:Female; D005315:Fetal Diseases / Q000097:blood / Q000000981:diagnostic imaging; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age / Q000378:metabolism*; D000072483:Placenta Growth Factor; D011225:Pre-Eclampsia / Q000175:diagnosis; D011237:Predictive Value of Tests; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000097:blood*; D011266:Pregnancy-Associated Plasma Protein-A / Q000378:metabolism; D011296:Prenatal Diagnosis / Q000379:methods*; D011446:Prospective Studies; D016216:Ultrasonography, Prenatal / Q000379:methods; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000378:metabolism*; D000509:alpha-Fetoproteins / Q000378:metabolism
chemical_list: D015415:Biomarkers; D018997:Chorionic Gonadotropin, beta Subunit, Human; C000608036:PGF protein, human; D011257:Pregnancy Proteins; D000509:alpha-Fetoproteins; D000072483:Placenta Growth Factor; D040281:Vascular Endothelial Growth Factor Receptor-1; D011266:Pregnancy-Associated Plasma Protein-A
keywords: free β-human chorionic gonadotropin; placental growth factor; pre-eclampsia; pregnancy-associated plasma protein-A; pyramid of antenatal care; small-for-gestational age; soluble fms-like tyrosine kinase-1; third-trimester screening