title: Bone status and associated factors measured by quantitative ultrasound in preterm and full-term newborn infants.
abstract: BACKGROUND
  A clear understanding of the factors associated with bone status in newborn infants is essential for devising strategies for preventing osteoporotic fracture in future generations.
  
  
  OBJECTIVE
  The aims of this study were to perform bone speed of sound (SOS) to assess the status of the tibia in preterm and full-term newborns, and to evaluate factors associated with bone status at birth.
  
  
  METHODS
  Bone SOS was measured by quantitative ultrasonography on the left tibia in full-term and preterm newborn infants immediately after birth. A birth chart and maternal history were recorded. Univariate and multivariate analyses were performed to identify factors affecting bone SOS at birth.
  
  
  METHODS
  The study analyzed 667 infants, including 370 males and 297 females, during study period.
  
  
  RESULTS
  Univariate analysis revealed that gender, gestational age (GA) and birth anthropometrics significantly affected tibial bone SOS at birth whereas maternal factors did not. Multivariate multiple regression analysis revealed that gender (male-to-female coefficient of 45.71 and 32.52 in premature and full-term infants, respectively), GA (coefficient of 32.55 and 31.27 in premature and full-term infants, respectively, for every 1-week increase), and birth weight (coefficient of -0.11 and -0.103 in premature and full-term infants, respectively, for every 1-gram increase) were important factors affecting tibial bone SOS in both preterm and full-term newborn infants at birth.
  
  
  CONCLUSIONS
  Male gender and advanced GA have a positive effect on increasing tibial bone SOS at birth, while birth weight had a negative effect on increasing tibial bone SOS. Tibial bone SOS is higher in small-for-gestational-age infants than in those of appropriate-for-gestational-age infants.
authors.affiliation: Department of Pediatrics, Kaohsiung Medical University Hospital, No.100 Tzyou 1st Road, San Ming, Kaohsiung, Taiwan.
authors.forename: Hsiu-Lin
authors.initials: HL
authors.lastname: Chen
authors.forename: Hsing-I
authors.initials: HI
authors.lastname: Tseng
authors.forename: San-Nan
authors.initials: SN
authors.lastname: Yang
authors.forename: Rei-Cheng
authors.initials: RC
authors.lastname: Yang
mesh_terms: D001724:Birth Weight; D015519:Bone Density; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007236:Infant, Small for Gestational Age; D008297:Male; D012737:Sex Factors; D013977:Tibia / Q000000981:diagnostic imaging*; D014463:Ultrasonography