title: Transvaginal three-dimensional ultrasound: accuracy of follicular volume measurements.
abstract: OBJECTIVE
  To evaluate the accuracy of three-dimensional (3-D) ultrasound (US) follicular volume measurements.
  
  
  METHODS
  Prospective clinical study.
  
  
  METHODS
  A tertiary referral center for assisted reproduction.
  
  
  METHODS
  Twenty-five patients undergoing ovarian stimulation for IVF-ET using the long protocol of GnRH agonist.
  
  
  METHODS
  Transvaginal two-dimensional (2-D) and 3-D ovarian scan performed immediately before US-directed follicle aspiration.
  
  
  METHODS
  The volume of follicular fluid aspirated was compared with the corresponding volume of the follicle measured by 3-D US and with the conventional 2-D US volume measurement calculated using the formula pi/6 (D1 x D2 x D3). Limits of agreement and 95% confidence intervals were calculated and systematic bias between the methods was analyzed.
  
  
  RESULTS
  The limits of agreement between the volume of follicular aspirate and follicular volume determined by US were +0.96 to -0.43 mL for 3-D measurements and +3.47 to -2.42 mL for 2-D measurements.
  
  
  CONCLUSIONS
  The true volume of ovarian follicles, within the clinically useful range for IVF-ET cycles, is measured more accurately by a 3-D US system than by 2-D US techniques.
authors.affiliation: London Women's Clinic, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Kyei-Mensah
authors.forename: J
authors.initials: J
authors.lastname: Zaidi
authors.forename: R
authors.initials: R
authors.lastname: Pittrof
authors.forename: A
authors.initials: A
authors.lastname: Shaker
authors.forename: S
authors.initials: S
authors.lastname: Campbell
authors.forename: S L
authors.initials: SL
authors.lastname: Tan
mesh_terms: D005260:Female; D015571:Follicular Fluid / Q000000981:diagnostic imaging*; D006801:Humans; D011446:Prospective Studies; D015203:Reproducibility of Results; D014463:Ultrasonography; D014621:Vagina