title: Factors leading to the removal of the intrauterine implant Gynefix.
abstract: OBJECTIVE
  The objective of this study was to determine the incidence of expulsion of the Gynefix intrauterine implant, to analyze the variables associated with the above and to examine the efficacy of this intrauterine contraceptive model in users at the Municipal Family Planning Center-SERGAS in A Coruña, Spain.
  
  
  METHODS
  A prospective observational study was performed on all women (n = 358) who had a Gynefix implant inserted from March 1998 to September 2000.
  
  
  RESULTS
  The accumulated incidence of implant expulsion was 6.7% (95% confidence interval (CI) 4.4-9.9) with a pregnancy rate of 0.6% (95% CI 0.09-2.2). The probability of implant removal decreases with the rise in the number of implants that have been inserted by the professional. A multivariate analysis adjusted for age, number of implants and uterine position showed that the position of the uterus was the variable that independently determined the probability of removal.
  
  
  CONCLUSIONS
  It is concluded that retroflexion of the uterus increases the probability of removal.
authors.affiliation: Municipal Family Planning Center-SERGAS, A Coruña, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Bonacho
authors.forename: M I
authors.initials: MI
authors.lastname: Gómez-Besteiro
authors.forename: S
authors.initials: S
authors.lastname: Pita
mesh_terms: D000293:Adolescent; D000328:Adult; D016001:Confidence Intervals; D003267:Contraception / Q000009:adverse effects / Q000379:methods; D020878:Device Removal; D005193:Family Planning Services; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007433:Intrauterine Device Expulsion / Q000009:adverse effects*; D007434:Intrauterine Devices / Q000706:statistics & numerical data*; D008875:Middle Aged; D011247:Pregnancy; D018873:Pregnancy Rate / Q000639:trends; D011275:Pregnancy, Unwanted / Q000706:statistics & numerical data*; D011336:Probability; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology