title: Fetal leg posture in uncomplicated breech and cephalic pregnancies.
abstract: BACKGROUND
  The objective of our study was to determine differences in prenatal leg posture development between breech and cephalic-born babies.
  
  
  METHODS
  Ten healthy fetuses in breech and ten healthy fetuses in cephalic presentation were observed by means of weekly ultrasounds from 33 weeks gestational age until birth to assess leg posture.
  
  
  RESULTS
  The breech fetuses showed a clear preference for an extended leg position; they spent significantly more time with their knees in extension than the cephalic fetuses (p<0.001). The cephalic fetuses showed significantly more leg-crossing than the breech fetuses (p<0.01). For both findings, no significant change over time could be observed in either group.
  
  
  CONCLUSIONS
  These findings show that the intra-uterine position does influence the fetal postural and motor development. However, it seems unlikely that intra-uterine movement restriction can solely be held accountable for the observed differences in leg position between breech and cephalic fetuses.
authors.affiliation: Research Institute MOVE, Faculty of Human Movement Sciences, VU University, Amsterdam, The Netherlands. b.f.fong@mca.nl
authors.forename: Bianca F
authors.initials: BF
authors.lastname: Fong
authors.forename: Geert J P
authors.initials: GJ
authors.lastname: Savelsbergh
authors.forename: Johanna I P
authors.initials: JI
authors.lastname: de Vries
mesh_terms: D000328:Adult; D001946:Breech Presentation / Q000000981:diagnostic imaging*; D016022:Case-Control Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D007866:Leg / Q000000981:diagnostic imaging* / Q000196:embryology*; D011187:Posture; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D016216:Ultrasonography, Prenatal