title: Correlation of ultrasound estimated placental volume and umbilical cord blood volume in term pregnancy.
abstract: OBJECTIVE
  To investigate the correlation between ultrasound measured placental volume and collected umbilical cord blood (UCB) volume in term pregnancy.
  
  
  METHODS
  An observational cross-sectional study of term singleton pregnant women in the labor ward at Maha Chakri Sirindhorn Medical Center was conducted. Placental thickness, height, and width were measured using two-dimensional (2D) ultrasound and calculated for placental volume using the volumetric mathematic model. After the delivery of the baby, UCB was collected and measured for its volume immediately. Then, birth weight, placental weight, and the actual placental volume were analyzed. The Pearson's correlation was used to determine the correlation between each two variables.
  
  
  RESULTS
  A total of 35 pregnant women were eligible for the study. The mean and standard deviation of estimated placental volume and actual placental volume were 534±180 mL and 575±118 mL, respectively. The median UCB volume was 140 mL (range 98-220 mL). The UCB volume did not have a statistically significant correlation with the estimated placental volume (correlation coefficient 0.15; p=0.37). However, the UCB volume was significantly correlated with the actual placental volume (correlation coefficient 0.62; p<0.001) and birth weight (correlation coefficient 0.38; p=0.02).
  
  
  CONCLUSIONS
  The estimated placental volume by 2D ultrasound was not significantly correlated with the UCB volume. Further studies to establish the correlation between the UCB volume and the estimated placental volume using other types of placental imaging may be needed.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok, Thailand.
authors.forename: Papinwit
authors.initials: P
authors.lastname: Pannopnut
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok, Thailand.
authors.forename: Maethaphan
authors.initials: M
authors.lastname: Kitporntheranunt
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok, Thailand.
authors.forename: Panwara
authors.initials: P
authors.lastname: Paritakul
authors.affiliation: Department of Preventive and Social Medicine, Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok, Thailand.
authors.forename: Kittipong
authors.initials: K
authors.lastname: Kongsomboon
keywords: Umbilical cord blood volume; placenta parameters; ultrasound