Thoughts on IMSI

ICSI achieves consistently high fertilization and pregnancy rates ­regardless of sperm characteristics and even azoospermic patients have fathered children by ICSI where spermatozoa were surgically retrieved. In this review, we report multicenter study results after the use of IMSI in patients with compromised semen parameters or in patients with previous ART failure using sibling oocytes. These studies, based on higher magnification screening for sperm surface irregularities, did not seem to benefit the patients’ clinical outcome in independent investigations. We conclude from these collaborative studies, IMSI does not bring any advantage in the quest to find spermatozoa devoid of surface irregularities and that it significantly lengthens the search time required.