Selection of individual sperm under high magnification microscope, (intracytoplasmic morphologically selected sperm injection or IMSI), allows the use of the most apparantly optimal sperm according to shape (morphology) in men with the most severe male factor.
IMSI is considered for patients with recurrent implantation failure or spontaneous miscarriages (Lo Monte et al. 2013) due to the opinion the pregnancy failures were due to a sperm defect. However, recent studies have opposed this view by showing IMSI does not improve outcomes for men undergoing multiple IVF cycles. (Oliveira et al. 2011, Gatimel et al. 2016).