title: First trimester umbilical cord and vessel diameters of Thai fetuses.
abstract: OBJECTIVE
  To establish the reference ranges for first trimester umbilical cord and vessel diameters of Thai fetuses.
  
  
  METHODS
  A prospective study was performed on normal pregnant women between 10(+0) and 13(+6) weeks of gestation who underwent ultrasound examination. The diameter measurements were obtained by a 7.5 MHz vaginal--or a 3.75 MHz abdominal transducer. Statistics were analyzed using SPSS computer program.
  
  
  RESULTS
  Records of 184 pregnancies were analyzed and the outcome demonstrated a strong correlation between umbilical cord diameter and gestational age (r = 0.90; p < 0.001). Umbilical vessel diameters were also correlated with gestational age.
  
  
  CONCLUSIONS
  First trimester umbilical cord and vessel diameters of Thai fetuses are related to gestational age. The presented reference ranges might be useful for further studies, such as prediction of adverse pregnancy outcome or combination with biochemical or other ultrasound markers for fetal aneuploidy screening.
authors.affiliation: Department of Obstetrics and Gynaecology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Chadakarn
authors.initials: C
authors.lastname: Phaloprakarn
authors.forename: Vorapong
authors.initials: V
authors.lastname: Phupong
authors.forename: Yuen
authors.initials: Y
authors.lastname: Tannirandorn
authors.forename: Boonchai
authors.initials: B
authors.lastname: Uerpairojkit
authors.forename: Dhiraphongs
authors.initials: D
authors.lastname: Charoenvidhya
authors.forename: Teera
authors.initials: T
authors.lastname: Wacharaprechanont
mesh_terms: D000328:Adult; D005260:Female; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011446:Prospective Studies; D012016:Reference Values; D013785:Thailand; D014463:Ultrasonography; D014469:Umbilical Arteries / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D014470:Umbilical Cord / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D014471:Umbilical Veins / Q000033:anatomy & histology / Q000000981:diagnostic imaging