The effect of ICSI-related procedural timings and operators on the outcome

A recent publication from a private IVF facility in Rome reports surprising findings in respect to ICSI-related procedural timings. The GENERA group reported on ICSI outcomes with fresh autologous oocytes where the insemination process was conducted with fresh non-donor ejaculated sperm. With primary outcome being the cumulative delivery rate (CDR) and secondary outcome the mean blastulation rate, the group showed that the latter was significantly higher when oocyte denudation for ICSI was performed less than 38 hours from ovulation induction rather than their usual 38-42 hours. Furthermore, they concluded that CDR was not influenced by ICSI timings where oocyte denudation was conducted between 2 to 7 hours from oocyte retrieval. This report has very significant implications for the logistical management of embryology laboratories, but most IVF clinics will be skeptical for two reasons – firstly the GENERA researchers failed to cite any of the early pioneer work regarding IVF insemination times, conducted from various locations in the 1980’s; all showing optimal outcomes when insemination was performed 5.5 to 7.5 hours post oocyte retrieval, matching around 42 hours post ovulation trigger. Secondly, the statistical analysis for their data was rather complex including multivariate logistic regression analyses which did not provide clearly conclusive results, certainly not sufficient to cause long-standing IVF operators to change practice. Within this era of evidence-based medicine, it is difficult to gain confidence in studies that appear to suggest nothing from the first 20 years of IVF was reliable.