title: 4D ultrasound evaluation of fetal facial expressions during the latter stages of the second trimester.
abstract: OBJECTIVE
  To assess the frequency of fetal facial expressions at 25-27 weeks of gestation using 4D ultrasound.
  
  
  METHODS
  Twenty-four normal fetuses were examined using 4D ultrasound. The face of each fetus was recorded continuously for 15 minutes. The frequencies of tongue expulsion, yawning, sucking, mouthing, blinking, scowling, and smiling were assessed and compared with those observed at 28-34 weeks of gestation in a previous study.
  
  
  RESULTS
  Mouthing was the most common facial expression at 25-27 weeks of gestation; the frequency of mouthing was significantly higher than that of the other 6 facial expressions (P<0.05). Yawning was significantly more frequent than the other facial expressions, apart from mouthing (P<0.05). The frequencies of yawning, smiling, tongue expulsion, sucking, and blinking differed significantly between 25-27 and 28-34 weeks (P<0.05).
  
  
  CONCLUSIONS
  The results indicate that facial expressions can be used as an indicator of normal fetal neurologic development from the second to the third trimester. 4D ultrasound may be a valuable tool for assessing fetal neurobehavioral development during gestation.
authors.affiliation: Department of Perinatology and Gynecology, Kagawa University School of Medicine, Miki, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kanenishi
authors.forename: Uiko
authors.initials: U
authors.lastname: Hanaoka
authors.forename: Junko
authors.initials: J
authors.lastname: Noguchi
authors.forename: Genzo
authors.initials: G
authors.lastname: Marumo
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Hata
mesh_terms: D005145:Face / Q000000981:diagnostic imaging*; D005149:Facial Expression; D005260:Female; D047109:Fetal Development / Q000502:physiology*; D005865:Gestational Age; D006801:Humans; D007089:Image Enhancement; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D016216:Ultrasonography, Prenatal / Q000379:methods*