title: Transcervical embryo transfer as a risk factor for ectopic pregnancy.
abstract: OBJECTIVE
  To evaluate the ease and timing of transcervical ET as risk factors for ectopic pregnancy (EP) after IVF.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  University-based IVF program in the United Kingdom.
  
  
  METHODS
  Eighteen consecutively seen patients with an EP after IVF and 314 patients with an intrauterine pregnancy after transcervical ET performed during the same period.
  
  
  METHODS
  Additional manipulation with a transfer catheter or the use of other instruments to assist transfer. Embryo transfer on day 2 or 3 after oocyte retrieval.
  
  
  METHODS
  Risk factors for EP (day 2 ET, difficult transfer overall and on days 2 and 3, history of tubal subfertility, and previous EP) presented as odds ratios with 95% confidence intervals.
  
  
  RESULTS
  The risk of EP was 2.26 (0.64-8.01) after day 2 ET, 3.91 (1.49-10.23) after difficult ET, 3.88 (1.34-11.24) after difficult ET on day 2, 2.7 (0.20-13.99) after difficult ET on day 3, 5.73 (1.99-16.62) when there was a history of tubal subfertility, and 5.41 (1.96-14.91) when there was a previous EP.
  
  
  CONCLUSIONS
  A difficult ET significantly increases the risk of an EP. The risk is particularly high when the patient has a history of tubal damage or previous EP. The timing of ET is important only if the ET is difficult.
authors.affiliation: Hull In Vitro Fertilization Unit, Princess Royal Hospital, East Yorkshire, United Kingdom.
authors.forename: P
authors.initials: P
authors.lastname: Lesny
authors.forename: S R
authors.initials: SR
authors.lastname: Killick
authors.forename: J
authors.initials: J
authors.lastname: Robinson
authors.forename: S D
authors.initials: SD
authors.lastname: Maguiness
mesh_terms: D002584:Cervix Uteri; D016001:Confidence Intervals; D004624:Embryo Transfer / Q000009:adverse effects* / Q000379:methods; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007247:Infertility, Female / Q000503:physiopathology; D016017:Odds Ratio; D011247:Pregnancy; D011271:Pregnancy, Ectopic / Q000453:epidemiology / Q000209:etiology*; D012189:Retrospective Studies; D012307:Risk Factors