title: Sonographic measurement of the umbilical cord and fetal anthropometric parameters.
abstract: OBJECTIVE
  To determine reference ranges for the diameter and the cross-sectional area of the umbilical cord during pregnancy and to determine if umbilical cord morphometry is related to fetal size.
  
  
  METHODS
  A prospective cross-sectional study was designed to assess the sonographic cross-sectional diameter and area of the umbilical cord. The sonographic umbilical cord measurements were obtained in a plane adjacent to the insertion of the cord into the fetal abdomen. Nomograms for the umbilical cord diameter and area were computed. Fetal biometry included: biparietal diameter, abdominal circumference, and femur length. Polynomial regression analysis was conducted.
  
  
  RESULTS
  Five hundred and fifty seven patients were included into the study. The regression equation for the umbilical cord diameter (y) according to gestational age (x) was y=-10.0563+1.4265x+0.0194x2 and for the umbilical cord area (y') was y'=91.6-3.3x+0.03x2-0.00007x3. A significant relationship was found between umbilical cord measurements and fetal anthropometric parameters.
  
  
  CONCLUSIONS
  Reference ranges for umbilical cord diameter and area have been generated. The sonographic diameter and cross-sectional area of the umbilical cord increase as a function of gestational age and both diameter and area correlate with fetal size.
authors.affiliation: The Department of Obstetrics and Gynecology, Kantonsspital, Münsterlingen, Switzerland.
authors.forename: L
authors.initials: L
authors.lastname: Raio
authors.forename: F
authors.initials: F
authors.lastname: Ghezzi
authors.forename: E
authors.initials: E
authors.lastname: Di Naro
authors.forename: R
authors.initials: R
authors.lastname: Gomez
authors.forename: M
authors.initials: M
authors.lastname: Franchi
authors.forename: M
authors.initials: M
authors.lastname: Mazor
authors.forename: H
authors.initials: H
authors.lastname: Brühwiler
mesh_terms: D000886:Anthropometry; D001699:Biometry / Q000379:methods; D003430:Cross-Sectional Studies; D005314:Embryonic and Fetal Development; D005260:Female; D005333:Fetus / Q000033:anatomy & histology; D006801:Humans; D011247:Pregnancy; D011446:Prospective Studies; D012044:Regression Analysis; D016216:Ultrasonography, Prenatal; D014470:Umbilical Cord / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*