title: Size of testes, ovaries, uterus and breast buds by ultrasound in healthy full-term neonates ages 0-3 days.
abstract: BACKGROUND
  Hormonally sensitive organs in the neonate can change size within days of birth as circulating maternal estrogen wanes. Although several reports document the size of these organs through infancy, few focus attention on the near-birth period. Clinical and research evaluation of hormonal and genitourinary disorders would benefit from reference size standards.
  
  
  OBJECTIVE
  We describe the size of the uterus, ovaries, testes and breast buds in healthy term neonates.
  
  
  METHODS
  As part of the Infant Feeding and Early Development (IFED) study, we sonographically measured the largest diameter of these organs in sagittal, transverse and anterior-posterior planes for 194 female and 204 male newborns up to 3 days old. We calculated mean, median and percentiles for longest axis length and for volume calculated from measured diameters. We evaluated size differences by laterality, gender and race and compared our observations against published values.
  
  
  RESULTS
  Mean length and mean volume were as follows: uterus, 4.2 cm and 10.0 cm3; ovary, 1.0 cm and 0.2 cm3; testis, 1.1 cm and 0.3 cm3(0.4 cm3Lambert volume); female breast bud, 1.2 cm and 0.7 cm3; male breast bud, 1.1 cm and 0.6 cm3. Breast buds were larger in females than males. Laterality differences were typically below the precision of clinical measurement. No significant race differences were detected.
  
  
  CONCLUSIONS
  Using data from our large cohort together with published values, we provide guidelines for evaluating the size of reproductive organs within the first 3 days of age. Discrepancies between our results and published values are likely attributable to technique.
authors: Department of Radiology, The Children's Hospital of Philadelphia, 34th Street & Civic Center Boulevard, Philadelphia, PA, 19104, USA. kaplans2@email.chop.edu.
authors: Summer L
authors: SL
authors: Kaplan
authors: Department of Radiology, The Children's Hospital of Philadelphia, 34th Street & Civic Center Boulevard, Philadelphia, PA, 19104, USA.|Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
authors: J Christopher
authors: JC
authors: Edgar
authors: Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
authors: Eileen G
authors: EG
authors: Ford
authors: Epidemiology Branch, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Research Triangle Park, NC, USA.
authors: Margaret A
authors: MA
authors: Adgent
authors: Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
authors: Joan I
authors: JI
authors: Schall
authors: Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.|Department of Pediatrics, Division of Endocrinology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
authors: Andrea
authors: A
authors: Kelly
authors: Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Research Triangle Park, NC, USA.
authors: David M
authors: DM
authors: Umbach
authors: Epidemiology Branch, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Research Triangle Park, NC, USA.
authors: Walter J
authors: WJ
authors: Rogan
authors: Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.|Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
authors: Virginia A
authors: VA
authors: Stallings
authors: Department of Radiology, The Children's Hospital of Philadelphia, 34th Street & Civic Center Boulevard, Philadelphia, PA, 19104, USA.|Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
authors: Kassa
authors: K
authors: Darge
mesh_terms: D059925:Anatomic Landmarks; D001940:Breast / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009929:Organ Size; D010053:Ovary / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D010414:Pennsylvania; D012016:Reference Values; D013737:Testis / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D014463:Ultrasonography / Q000379:methods*; D014599:Uterus / Q000033:anatomy & histology / Q000000981:diagnostic imaging*
keywords: Breast; Measurements; Neonate; Ovary; Testis; Ultrasound; Uterus