Could sperm grade under high magnification condition predict IMSI clinical outcome?

ObjectiveThe aim of this study was to examine whether injection of first-best morphology grade selected spermatozoa improves live birth rate (LBR) compared to intracytoplasmic morphologically selected sperm injection (IMSI) using second-best grade sperm.Study designIn this prospective observational study, 132 patients were enrolled. Inclusion criteria were the presence of severe male factor (normal spermatozoa <10% in fresh ejaculated semen and <10% in selected sperm according to David's classification) associated with ≤2 previous ICSI failure. Results of IMSI performed with either first- or second-best morphology grade spermatozoa (according to Vanderzwalmen's classification) were compared. IMSI attempts performed using mixed first- and second-best grade spermatozoa were excluded (n = 41). The primary endpoint was LBR.ResultsLBR following IMSI was not statistically different using first- (33.3% (13/39)) or second-best morphology grade spermatozoa (28.9% (15/52)). Our study shows that sperm grading under high magnification using Vanderzwalmen's classification is not correlated to IMSI outcome.ConclusionWe do not validate Vanderzwalmen classification in our external and prospective series. These results point out the need for improving our knowledge about the impact of observed vacuoles under high magnification condition.