Use of testicular versus ejaculated sperm for intracytoplasmic sperm injection among men with cryptozoospermia: a meta-analysis

Objective: To examine outcomes of intracytoplasmic sperm injection (ICSI) using testicular versus ejaculated sperm among men with cryptozoospermia.

Design: Meta-analysis.

Setting: Not applicable.

Patient(s): Men with cryptozoospermia undergoing consecutive ICSI cycles using ejaculated or testicular sperm.

Intervention(s): 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.

Main outcome measure(s): 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).

Result(s): 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.

Conclusion(s): The existing literature does not support a recommendation for men with cryptozoospermia to use testicular sperm in preference over ejaculated sperm for ICSI.