title: Divergence of estimated fetal weight and birth weight in singleton fetuses.
abstract: OBJECTIVE
  To evaluate differences in distribution of estimated fetal weight (EFW) and birth weight (BW) of ongoing fetuses and neonates of the same gestational age.
  
  
  METHODS
  Reference curves for EFW (Hadlock BPD-HC-AC-FL formula, N = 1191) and BW (N = 1036) in singleton pregnancies from 24+0to 40+6gestational weeks were calculated. Multiple pregnancies, fetuses with major or multiple abnormalities or syndromes and iatrogenic preterm deliveries due to preeclampsia or abnormal fetal Doppler were excluded. The standardized residuals for EFW and BW were calculated and compared.
  
  
  RESULTS
  EFW and BW can be accurately described by quadratic equations (R2= 0.944 and 0.807, respectively). The distribution of standardized residuals for BW using the EFW formula was negative from 28+0to 35+6weeks. The 50th and 5th centiles of BW were lower than those of EFW throughout prematurity, and they converged at approximately 38 gestational weeks. The 5th centile for BW was 30% lower than the 5th centile for EFW at 27 weeks, 27.5% lower at 30 weeks and 19.4% at 34 weeks.
  
  
  CONCLUSIONS
  Preterm infants have lower BW distribution compared to the expected EFW of ongoing pregnancies of the same gestational age, supporting the concept of hidden intrauterine morbidity for a proportion of these infants.
authors.affiliation: a Second Department of Obstetrics and Gynecology , Aristotle University of Thessaloniki , Thessaloniki , Greece.
authors.forename: Alexandros
authors.initials: A
authors.lastname: Sotiriadis
authors.affiliation: b Second Department of Obstetrics and Gynecology , National and Kapodistrian University of Athens , Athens , Greece.
authors.forename: Makarios
authors.initials: M
authors.lastname: Eleftheriades
authors.affiliation: c Department of Obstetrics and Gynecology , University of Patras , Patras , Greece.
authors.forename: Vassileios
authors.initials: V
authors.lastname: Papadopoulos
authors.affiliation: d First Department of Neonatology - Neonatal Intensive Care Unit , Aristotle University of Thessaloniki , Thessaloniki , Greece.
authors.forename: Kosmas
authors.initials: K
authors.lastname: Sarafidis
authors.affiliation: e First Department of Pediatrics , National and Kapodistrian University of Athens , Athens , Greece.
authors.forename: Panagiota
authors.initials: P
authors.lastname: Pervanidou
authors.affiliation: a Second Department of Obstetrics and Gynecology , Aristotle University of Thessaloniki , Thessaloniki , Greece.
authors.forename: Efstratios
authors.initials: E
authors.lastname: Assimakopoulos
mesh_terms: D000328:Adult; D001724:Birth Weight; D003430:Cross-Sectional Studies; D005260:Female; D047109:Fetal Development / Q000502:physiology*; D020567:Fetal Weight; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D011247:Pregnancy; D012016:Reference Values; D012044:Regression Analysis; D017678:Sex Distribution; D016216:Ultrasonography, Prenatal / Q000379:methods; D055815:Young Adult
keywords: Fetal growth; birth weight; reference curves