title: Placental volume at 11-13 weeks' gestation in the prediction of birth weight percentile.
abstract: OBJECTIVE
  To determine the value of placental volume measured by 3D ultrasound at 11-13 weeks' gestation in combination with maternal characteristics and serum pregnancy-associated plasma protein-A (PAPP-A) in the prediction of small and large for gestational age (SGA and LGA) neonates.
  
  
  METHODS
  Maternal serum PAPP-A and placental volume were measured at 11-13 weeks in 3,104 singleton pregnancies. Regression analysis was used to examine the contribution of maternal characteristics, placental volume and PAPP-A in the prediction of SGA and LGA neonates.
  
  
  RESULTS
  There was a significant association between placental volume and PAPP-A (r = 0.268, p < 0.0001). Median placental volume and PAPP-A, expressed as multiples of the median (MoM) in appropriate for gestational age (AGA) neonates, were reduced in the SGA group (placental volume 0.88 MoM, vs. 1.00 MoM in AGA, p < 0.0001; PAPP-A 0.92 MoM vs. 1.00 MoM in AGA, p = 0.019) and increased in the LGA group (placental volume 1.09 MoM vs. 1.00 MoM in AGA, p < 0.0001; PAPP-A 1.15 MoM vs. 1.00 MoM in AGA, p = 0.015). Maternal characteristics with either placental volume or PAPP-A detected about 30% of the SGA or LGA neonates, at a false positive rate of 10%.
  
  
  CONCLUSIONS
  Measurement of placental volume and serum PAPP-A can improve the prediction of SGA or LGA neonates provided by maternal characteristics alone.
authors.affiliation: Harris Birthright Research Centre, Kings College Hospital, London, UK.
authors.forename: Walter
authors.initials: W
authors.lastname: Plasencia
authors.forename: Ranjit
authors.initials: R
authors.lastname: Akolekar
authors.forename: Themistoklis
authors.initials: T
authors.lastname: Dagklis
authors.forename: Alina
authors.initials: A
authors.lastname: Veduta
authors.forename: Kypros H
authors.initials: KH
authors.lastname: Nicolaides
mesh_terms: D000328:Adult; D001724:Birth Weight; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D010920:Placenta / Q000000981:diagnostic imaging* / Q000502:physiology; D011247:Pregnancy / Q000502:physiology*; D011261:Pregnancy Trimester, First; D011266:Pregnancy-Associated Plasma Protein-A / Q000378:metabolism; D016216:Ultrasonography, Prenatal
chemical_list: D011266:Pregnancy-Associated Plasma Protein-A