title: Impact of three-dimensionally measured endometrial volume on the pregnancy rate after intrauterine insemination.
abstract: OBJECTIVE
  The success of artificial reproductive techniques not only depends on the quality of oocytes and spermatozoa but also on the receptivity of the endometrium. The aim of this study was to assess the role of endometrial volume measurement by three-dimensional ultrasound in predicting the pregnancy rate (PR) in women receiving controlled ovarian hyperstimulation followed by intrauterine insemination.
  
  
  METHODS
  104 patients having intrauterine insemination (IUI) were included in this prospective trial. Ovarian hyperstimulation was performed with gonadotropins in 73 % of patients and with clomiphene citrate (CC) in 27 % of patients. Endometrial thickness, pattern and three-dimensional volume were measured immediately before insemination.
  
  
  RESULTS
  In 104 IUI cycles a total of 14 clinical pregnancies were recorded (PR=13.5 %). The endometrial volume was 3.5 ml and was not significantly different in pregnant (4.0 +/- 1.5 ml) from non-pregnant women (3.4 +/- 1.9 ml). In the subgroup of women with an endometrial volume > or = 2 ml and trilaminar endometrium the pregnancy rate was 22 %, significantly higher than that in women without these two criteria (PR 6 %, p < 0.05). The negative predictive value of an endometrial volume < 2 ml for a clinical pregnancy after IUI was 96 %. Endometrial volume and thickness were significantly higher after ovarian hyperstimulation with gonadotropins (3.7 ml and 11.0 mm) than with CC (2.8 ml and 9.5 mm; p < 0.05).
  
  
  CONCLUSIONS
  An endometrial volume < 2 ml at the day of insemination is associated with a poor likelihood of pregnancy. Endometrial volume measured by 3D ultrasound is a new objective parameter to predict endometrial receptivity.
authors.affiliation: Department of Obstetrics and Gynecology, University of Würzburg, Josef-Schneider-Strasse 4, 97080 Würzburg. zollner_u@klinik.uni-wuerzburg.de
authors.forename: U
authors.initials: U
authors.lastname: Zollner
authors.forename: K-P
authors.initials: KP
authors.lastname: Zollner
authors.forename: S
authors.initials: S
authors.lastname: Blissing
authors.forename: U
authors.initials: U
authors.lastname: Pöhls
authors.forename: T
authors.initials: T
authors.lastname: Steck
authors.forename: J
authors.initials: J
authors.lastname: Dietl
authors.forename: T
authors.initials: T
authors.lastname: Müller
mesh_terms: D000328:Adult; D004717:Endometrium / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007248:Infertility, Male / Q000453:epidemiology; D007316:Insemination, Artificial, Heterologous; D007317:Insemination, Artificial, Homologous; D008297:Male; D009845:Oligospermia / Q000453:epidemiology; D011247:Pregnancy; D011256:Pregnancy Outcome; D014463:Ultrasonography
chemical_list: D005640:Follicle Stimulating Hormone