title: Prenatal midtrimester fetal long bone measurements and the prediction of small-for-gestational-age fetuses at term.
abstract: OBJECTIVE
  To determine if the length of fetal long bones (LB) at mid-trimester ultrasound is predictive of small-for-gestational-age (SGA) newborns at term delivery.
  
  
  METHODS
  Retrospective evaluation of 6,781 women between 18 and 24 weeks' gestation at Magee-Womens Hospital (MWH). Gestational age (GA) was confirmed by first- or second-trimester ultrasound and patient's last menstrual period. Data were accrued from the institutional database at MWH. LB measurements were normalized to GA at the time of the ultrasound. The ratio was correlated with the probability of delivering an SGA newborn at term.
  
  
  RESULTS
  In all, 583 women were identified with an SGA newborn (8.6%). LB-to-GA ratios were associated with the probability of delivering an SGA newborn at term (p < 0.001). There was no single LB that proved to be superior in predicting an SGA newborn.
  
  
  CONCLUSIONS
  There is a significant association between LB-to-GA ratio at midtrimester and the probability of SGA at term.
authors.affiliation: Division of Ultrasound, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Speer
authors.affiliation: Division of Ultrasound, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
authors.forename: Timothy
authors.initials: T
authors.lastname: Canavan
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
authors.forename: Hyagriv N
authors.initials: HN
authors.lastname: Simhan
authors.affiliation: Division of Ultrasound, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
authors.forename: Lyndon M
authors.initials: LM
authors.lastname: Hill
mesh_terms: D000293:Adolescent; D000328:Adult; D050280:Arm Bones / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D005260:Female; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D007867:Leg Bones / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D016014:Linear Models; D008875:Middle Aged; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal; D055815:Young Adult