title: Ultrasound assessment of haemoperitoneum in ectopic pregnancy: derivation of a prediction model.
abstract: BACKGROUND
  To derive an ultrasound-based prediction model for the quantification of haemoperitoneum in ectopic pregnancy (EP).
  
  
  METHODS
  Retrospective study of 89 patients operated upon EP between January 1999 and March 2003 in a French Gynaecology and Obstetrics department in a university hospital. Transvaginal sonograms, clinical and biological variables from patients with haemoperitoneum >/= 300 ml at surgery were compared with those from patients with haemoperitoneum < 300 ml or no haemoperitoneum. Sensitivity, specificity, positive and negative likelihood ratios were calculated for each parameter after appropriate dichotomization. Multiple logistic regression analysis was used to select the best combination at predicting haemoperitoneum >/= 300 ml.
  
  
  RESULTS
  Three parameters predicted haemoperitoneum >/= 300 ml independently: moderate to severe spontaneous pelvic pain, fluid above the uterine fundus or around the ovary at transvaginal ultrasound, and serum haemoglobin concentration < 10 g/dL. A woman with none of these three criteria would have a probability of 5.3% for haemoperitoneum >/= 300 ml. When two or more criterias were present, the probability for haemoperitoneum >/= 300 ml reached 92.6%.
  
  
  CONCLUSIONS
  The proposed model accurately predicted significant haemoperitoneum in patients diagnosed to have EP.
authors.affiliation: Department of Gynaecology, Obstetrics and Reproductive medicine, CHI Poissy-St-Germain, Saint-Germain-En-Laye, France. afauconnier@chi-poissy-st-germain.fr.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Fauconnier
authors.forename: Ali
authors.initials: A
authors.lastname: Mabrouk
authors.forename: Laurent J
authors.initials: LJ
authors.lastname: Salomon
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Bernard
authors.forename: Yves
authors.initials: Y
authors.lastname: Ville