title: Fetal cerebral ventricular atrium: difference in size according to sex.
abstract: OBJECTIVE
  To determine whether the diameter of the fetal lateral ventricular atrium is larger in male than in female fetuses.
  
  
  METHODS
  The atrial diameter in 219 fetuses retrospectively identified from a consecutive group of healthy newborns was measured without knowledge of the subject's sex.
  
  
  RESULTS
  Atrial size demonstrated a near-normal distribution, with mean size for all subjects 6.1 mm +/- 1.3 (standard deviation). When separated by sex, the mean atrial diameter of 122 female fetuses was 5.8 mm +/- 1.3, and the mean atrial diameter of 97 male fetuses was 6.4 mm +/- 1.3. The difference in mean size is statistically significant (P < .005).
  
  
  CONCLUSIONS
  Male fetuses have a slightly larger atrial size than female fetuses. This discovery has implications for defining the upper limit of normal for fetal ventricular atrial size.
authors.affiliation: Department of Radiology, San Francisco General Hospital, University of California 94143.
authors.forename: M D
authors.initials: MD
authors.lastname: Patel
authors.forename: R B
authors.initials: RB
authors.lastname: Goldstein
authors.forename: S
authors.initials: S
authors.lastname: Tung
authors.forename: R A
authors.initials: RA
authors.lastname: Filly
mesh_terms: D002552:Cerebral Ventricles / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000196:embryology*; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011247:Pregnancy; D012016:Reference Values; D012189:Retrospective Studies; D012727:Sex Characteristics; D016216:Ultrasonography, Prenatal