title: Bone measurements of infants in the first 3 months of life by quantitative ultrasound: the influence of gestational age, season, and postnatal age.
abstract: BACKGROUND
  There are a few quantitative ultrasound (QUS) studies of bone status for Chinese children.
  
  
  OBJECTIVE
  To evaluate the clinical application and to investigate the bone status of neonates and young infants with QUS.
  
  
  METHODS
  An ultrasound bone sonometer was used to measure the bone speed of sound (SOS) of the tibia in 542 neonates within 3 months of birth.
  
  
  RESULTS
  At birth, no significant difference of SOS was found between boys and girls, but there was a significant difference of SOS between premature infants and full-term infants. The SOS in neonates born during spring and summer was significantly lower than those born during autumn and winter. There were significant correlations between SOS and gestational age, and between bone SOS and birth weight in appropriate for gestational age (AGA) infants. Multiple regression analysis found that gestational age and infant birth season were two important factors influencing SOS. During the first 3 months, there was no significant difference in SOS between sexes. The SOS of infants showed an inverse correlation with postnatal age, and the decrease of bone SOS with age in premature infants was more marked than in full-term infants.
  
  
  CONCLUSIONS
  QUS is suitable for evaluating bone status in infants with high precision. The study offers some basic data for neonates and young infants.
authors.affiliation: Division of Nutrition, Shanghai Institute for Pediatric Research, Shanghai Xinhua Hospital, Shanghai Second Medical University, 1665 Kong Jiang Road, Shanghai 200092, China.
authors.forename: Xiang-Peng
authors.initials: XP
authors.lastname: Liao
authors.forename: Wei-Li
authors.initials: WL
authors.lastname: Zhang
authors.forename: Jiamin
authors.initials: J
authors.lastname: He
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Sun
authors.forename: Ping
authors.initials: P
authors.lastname: Huang
mesh_terms: D000367:Age Factors; D000704:Analysis of Variance; D001846:Bone Development / Q000502:physiology*; D002681:China; D005260:Female; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D012044:Regression Analysis; D012621:Seasons; D012737:Sex Factors; D013977:Tibia / Q000000981:diagnostic imaging*; D014463:Ultrasonography