title: Use of testicular versus ejaculated sperm for intracytoplasmic sperm injection among men with cryptozoospermia: a meta-analysis.
abstract: OBJECTIVE
  To examine outcomes of intracytoplasmic sperm injection (ICSI) using testicular versus ejaculated sperm among men with cryptozoospermia.
  
  
  METHODS
  Meta-analysis.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Men with cryptozoospermia undergoing consecutive ICSI cycles using ejaculated or testicular sperm.
  
  
  METHODS
  A systematic search was performed using PubMed (inception to August 2015). Inclusion criteria were studies comparing ICSI outcomes among men with cryptozoospermia using ejaculated and testicular sperm.
  
  
  METHODS
  Primary outcomes included ICSI fertilization or pregnancy rates (PRs). Secondary analysis included number of retrieved oocytes, maternal and paternal ages. Meta-analysis of weighted data using a random effects model was performed. Results are reported as relative risk or weighted mean differences (WMD) with 95% confidence intervals (CI).
  
  
  RESULTS
  Five cohort studies were included, encompassing 272 ICSI cycles and 4,596 injected oocytes. There were no differences in ICSI PRs (relative risk [RR] 0.53, 95% CI 0.19-1.42, I(2) = 67%) or fertilization rates (RR 0.91, 95% CI 0.78-1.06, I(2) = 73%) between testicular and ejaculated sperm groups. There was a significant trend toward increasing maternal age (WMD 1.69 years, 95% CI -2.71 to -0.66) and paternal age (WMD 2.61 years, 95% CI -4.73 to -0.48) with testicular sperm. There was no difference between numbers of oocytes retrieved (WMD 0.95, 95% CI -0.15 to 2.05). Post-hoc power analysis revealed pβ <20% for PR analysis and pβ <10% for fertilization rate analysis.
  
  
  CONCLUSIONS
  The existing literature does not support a recommendation for men with cryptozoospermia to use testicular sperm in preference over ejaculated sperm for ICSI.
authors.affiliation: Department of Urology, University of Illinois at Chicago, Chicago, Illinois. Electronic address: nikitaa@uic.edu.
authors.forename: Nikita
authors.initials: N
authors.lastname: Abhyankar
authors.affiliation: Division of Urology, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Martin
authors.initials: M
authors.lastname: Kathrins
authors.affiliation: Department of Urology, University of Illinois at Chicago, Chicago, Illinois.
authors.forename: Craig
authors.initials: C
authors.lastname: Niederberger
mesh_terms: D053713:Azoospermia / Q000175:diagnosis / Q000628:therapy*; D015331:Cohort Studies; D004542:Ejaculation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D018873:Pregnancy Rate / Q000639:trends; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods*; D053625:Sperm Retrieval; D013094:Spermatozoa / Q000502:physiology* / Q000637:transplantation; D013737:Testis / Q000502:physiology*
keywords: Cryptozoospermia; intracytoplasmic sperm injection; testicular sperm