title: First-trimester hand measurements in euploid and aneuploid human fetuses using virtual reality.
abstract: OBJECTIVE
  Although second-trimester and third-trimester reference curves for human fetal hand growth allow for identification of several genetic syndromes, little is known about first-trimester hand growth. We investigated first-trimester hand growth in euploid and aneuploid fetuses.
  
  
  METHODS
  Between 9 and 12 weeks' gestational age (GA), wrist width, hand width, hand length, and hand index were measured in three-dimensional (3D) ultrasound datasets of 112 euploid and 65 aneuploid pregnancies. We constructed reference curves for these measurements in euploid pregnancies and calculated z-scores for measurements in aneuploid pregnancies. Reproducibility was established in a subset of 20 datasets.
  
  
  RESULTS
  While wrist width, hand width, and hand length increased with gestational age, hand index decreased. Intraobserver and interobserver intraclass correlation coefficient values were >0.97. In trisomy 21 cases, wider wrists and hands were observed compared with euploid pregnancies (mean z-scores 1.06, SD 2.04, p < 0.001 and 1.16, SD 1.30, p < 0.001, respectively). Trisomy 18 cases showed narrower and shorter hands (mean z-scores -0.74, SD 1.20, p = 0.009 and -0.97, SD 0.86, p = 0.005, respectively). In trisomy 13 cases, no differences were observed.
  
  
  CONCLUSIONS
  Reference values are available for first-trimester studies on human hand development. First-trimester hand measurements in trisomies 21 and 18 differ significantly from those in euploid pregnancies and may be useful for early identification of abnormal development.
authors.affiliation: Department of Obstetrics and Gynaecology, Division of Obstetrics and Prenatal Medicine, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands.
authors.forename: Leonie
authors.initials: L
authors.lastname: Baken
authors.forename: Bernard
authors.initials: B
authors.lastname: Benoit
authors.forename: Anton H J
authors.initials: AH
authors.lastname: Koning
authors.forename: Sten P
authors.initials: SP
authors.lastname: Willemsen
authors.forename: Peter J
authors.initials: PJ
authors.lastname: van der Spek
authors.forename: Régine P M
authors.initials: RP
authors.lastname: Steegers-Theunissen
authors.forename: Eric A P
authors.initials: EA
authors.lastname: Steegers
authors.forename: Niek
authors.initials: N
authors.lastname: Exalto
mesh_terms: D000328:Adult; D000782:Aneuploidy; D005260:Female; D006225:Hand / Q000000981:diagnostic imaging*; D006228:Hand Deformities, Congenital / Q000000981:diagnostic imaging*; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012016:Reference Values; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal; D055815:Young Adult