title: Early pregnancy loss in women stimulated with gonadotropin-releasing hormone antagonist protocols according to oral contraceptive pill pretreatment.
abstract: OBJECTIVE
  To evaluate and compare the risk of early pregnancy loss in patients stimulated with GnRH antagonist protocols according to oral contraceptive pill (OCP) pretreatment.
  
  
  METHODS
  Retrospective case-control study.
  
  
  METHODS
  Instituto Valenciano de Infertilidad. University of Valencia. Spain.
  
  
  METHODS
  One thousand five hundred thirty-nine patients, aged <36, stimulated with GnRH antagonists for IVF between January 1, 2000 and November 1, 2005.
  
  
  METHODS
  Reproductive outcome was compared based on the application (or not) of OCP pretreatment: 944 women were included in the OCP group and 595 in the non-OCP group. The Student's t test was used for statistics.
  
  
  METHODS
  Pregnancy, biochemical pregnancy, ectopic pregnancy, early clinical pregnancy loss, early pregnancy loss, and ongoing pregnancy rates.
  
  
  RESULTS
  No significant differences were observed in any of the outcome parameters. Early pregnancy loss rates were similar: 23% in the OCP pretreatment group versus 19.2% in the non-OCP pretreatment group. However, longer periods of ovarian stimulation and higher doses of gonadotropins needed to be employed in the OCP group.
  
  
  CONCLUSIONS
  There is not sufficient evidence to confirm OCP pretreatment as a risk factor for miscarriage in patients stimulated with GnRH antagonist protocols.
authors.affiliation: Instituto Valenciano de Infertilidad, Universidad de Valencia, Valencia, Spain. jbellver@ivi.es <jbellver@ivi.es>
authors.forename: José
authors.initials: J
authors.lastname: Bellver
authors.forename: Carmen
authors.initials: C
authors.lastname: Albert
authors.forename: Elena
authors.initials: E
authors.lastname: Labarta
authors.forename: Antonio
authors.initials: A
authors.lastname: Pellicer
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003276:Contraceptives, Oral / Q000008:administration & dosage* / Q000009:adverse effects; D020964:Embryo Loss / Q000139:chemically induced / Q000453:epidemiology*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors* / Q000502:physiology; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies
chemical_list: D003276:Contraceptives, Oral; D007987:Gonadotropin-Releasing Hormone