title: Predictive factors for multiple pregnancy in in vitro fertilization.
abstract: OBJECTIVE
  To study predictive factors influencing the multiple pregnancy rate in in vitro fertilization (IVF).
  
  
  METHODS
  Retrospective study.
  
  
  RESULTS
  In 1,736 IVF cycles, 453 pregnancies occurred. The rate of singleton, twin and triplet pregnancies was 44%, 22% and 4.5%, respectively. Eighty-one percent of these clinical pregnancies ended with a delivery, giving a "take-home baby" rate of 23.8%/oocyte retrieval. As expected, a statistically significant positive correlation was found between the number and quality of embryos replaced and the occurrence of multiple pregnancies. A statistically significant correlation was also found when parameters such as age, stimulation parameters and embryo characteristics were incorporated into the analysis. This correlation was different for singleton, twin and triplet pregnancies.
  
  
  CONCLUSIONS
  Based on the findings of this study, in patients with a good prognosis for IVF outcome, only two embryos of good quality should be replaced regardless of the maternal age or number of IVF attempts.
authors.affiliation: Department of Gynecology, University Hospital St. Luc, Catholic University of Louvain, Brussels, Belgium. bassil@gyne.ucl.be
authors.forename: S
authors.initials: S
authors.lastname: Bassil
authors.forename: C
authors.initials: C
authors.lastname: Wyns
authors.forename: D
authors.initials: D
authors.lastname: Toussaint-Demylle
authors.forename: W
authors.initials: W
authors.lastname: Abdelnour
authors.forename: J
authors.initials: J
authors.lastname: Donnez
mesh_terms: D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007246:Infertility / Q000628:therapy; D016015:Logistic Models; D008423:Maternal Age; D010062:Ovulation Induction; D011247:Pregnancy; D011272:Pregnancy, Multiple; D011379:Prognosis; D012189:Retrospective Studies; D014310:Triplets; D014427:Twins