How to select immotile but viable spermatozoa on the day of intracytoplasmic sperm injection? An embryologist's view

Abstract

SUMMARYA viable spermatozoon is the prerequisite for initiating fertilization in intracytoplasmic sperm injection. Usually motility is the primary sign used to determine a sperm's viability. However, in every in vitro fertilization (IVF) laboratory cases are observed in which none or only few spermatozoa are motile. This can occur in treatment cycles involving ejaculated samples but is most common in cases where surgically extracted testicular spermatozoa are used. To aid in selection, several techniques have been developed to identify viable spermatozoa from the immotile fraction. Amongst the more commonly used approaches are (i) the hypo-osmotic swelling test (ii) chemical substances for induction of tail movements (iii) the sperm tail flexibility test and (iv) laser-assisted immotile sperm selection. All can be used routinely in an IVF laboratory with each having both strengths and weaknesses. It is the purpose of this short review to focus on the technical issues involved in the performance of each of these techniques and to highlight the advantages and disadvantages of each approach.

Processing and selection of surgically-retrieved sperm for ICSI: a review

“…The use of the laser has the advantage that it does not require any chemical compound to induce motility, and thereby may be considered a safer approach. The main obstacle to its widespread application remains the high cost of the equipment needed [68]. …”

A Stimulatory Approach for in Vitro Activation of Human Sperm Motility by Using Theophylline.

“…SpermMobil dilution resulted in least reduction in sperm concentration that may be due to beneficial effect of its components and a short incubation time, ten minute required for SpermMobil action was useful for sperm yield (9) .In vitro sperm activation with FertiCult medium led to enhance of progressive sperm motility and MNS as compared with without activation, this due to their aqueous nature with lower viscosity than of seminal plasma resulted in making movement of sperm more freely in culture medium (10) , FertiCult Flushing medium contain many components needed in physiology and metabolism of sperm such as serum albumin which contains cysteine-34; may act to capture radicals, that is critical for maintaining MNS. Regarding improvement of sperm motility, in healthy subjects and asthenozoospermic patients study after being activated by Theophylline solution, these results were in an agreement with results of Loughlin et al (3) ,Theophylline has ability on inhibition of PDE activity and thus increasing cAMP level which play a main role in glycolytic pathways of sperm, it can influence on energy generation for sperm motility.…”

A successful pregnancy using completely immotile but viable frozen-thawed spermatozoa selected by laser

“…However, it is unclear whether immotile spermatozoa are worth cryopreserving for further ICSI. The selection of immotile but viable spermatozoa on the day of ICSI is a major challenge for embryologists [14]. …”