title: [Treatment option for unexplained primary infertility following failed intrauterine insemination].
abstract: OBJECTIVE
  To determine an optimal insemination technique for unexplained infertility patients undergoing IVF or ICSI following failed intrauterine insemination (IUI).
  
  
  METHODS
  Sixty-five cycles of 61 patients with failed IUI were divided into four groups: Group A (37 cycles of IVF), Group B (19 cycles of ICSI), Group C (4 cycles of IVF and ICSI: half and half), Group D (5 cycles of ICSI after failed IVF). The conventional IVF cycles were defined as Group E (37 cycles), and the conventional ICSI cycles defined as Group F (24 cycles). The fertilization rate, completely failed fertilization rate, high quality embryo rate, clinical pregnancy rate and the implantation rate were compared among all the groups.
  
  
  RESULTS
  There were statistically significant differences in the fertilization rate, completely failed fertilization rate between Groups A and E (55.4% vs 72.8%, P < 0.05; 21.6% vs 0%, P < 0.005), and Groups A and B (55.4% vs 68.4%, P < 0.05; 21.6% vs 0%, P < 0.01). In Group D, there was statistically significant difference in the fertilization rate between IVF cycles and ICSI cycles (12.2% vs 74.2%, P < 0.005).
  
  
  CONCLUSIONS
  The present study demonstrates that there may be 20% of totally failed fertilization in IVF cycles with unexplained primary infertility following failed IUI, and ICSI treatment can increase fertilization rate and avoid complete fertilization failure.
authors.affiliation: Reproductive Medicine Center, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ding
authors.forename: Jiayin
authors.initials: J
authors.lastname: Liu
authors.forename: Yun
authors.initials: Y
authors.lastname: Qian
authors.forename: Naiming
authors.initials: N
authors.lastname: Yang
authors.forename: Yundong
authors.initials: Y
authors.lastname: Mao
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000209:etiology / Q000628:therapy*; D007317:Insemination, Artificial, Homologous / Q000379:methods*; D008297:Male; D010062:Ovulation Induction; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods*; D017211:Treatment Failure