Sperm morphology and its disorders in the context of infertility

Abstract

This manuscript reviews sperm morphology and its disorders in the context of infertility. A new look into an old challenge is delivered, based on contemporary scientific and clinical evidence. We highlight the functional repercussions of sperm morphology aberrations and dissect the cause and effect of a variety of insults and pathogenic mechanisms focusing on the relationships among sperm shape, function, and compartmental analysis of cellular and subcellular structures. Different types of teratozoospermia are identified as a sequela of aberrant spermiogenesis, and their proven or speculated origins are discussed. In addition to known and suspected genetic causes, oxidative damage is highlighted as a major plausible pathogenic factor. The examination of sperm morphology with the use of strict criteria provides valuable information to guide the clinician to direct therapeutic management. We emphasize that sperm morphology is probably the most relevant parameter of the traditional semen evaluation and can be used as a valid biomarker of functional deficiencies, providing information about chances of conception. The information provided by the examination of sperm morphology as part of a complete semen analysis becomes more and more significant from a clinical point of view for infertility and perhaps men's health. (Fertil Steril Rev Ò 2021;2:75-92. Ó2020 by American Society for Reproductive Medicine.

A Bayesian analysis of boar spermatozoa kinematics and head morphometrics and their relationship with litter size fertility variables

“…This relationship is supported by studies on DNA packaging that concluded that good chromatin condensation is correlated with morphological and morphometric variables (Carreira et al, 2015;R. V. De Oliveira et al, 2013;Gaggini et al, 2017;Gama Campos et al, 2013;Hammadeh et al, 1999;Ioannou et al, 2016;Oehninger & Kruger, 2020;Razavi et al, 2020). Our results suggest that morphometric variables have relevant differences between sire lines;…”

“…The sperm head size is linked to genes, and purebreds have been reported to have smaller spermatozoa than crossbreds (Wysokińska & Kondracki, 2019). This relationship is supported by studies on DNA packaging that concluded that good chromatin condensation is correlated with morphological and morphometric variables (Carreira et al., 2015; R. V. De Oliveira et al., 2013; Gaggini et al., 2017; Gama Campos et al., 2013; Hammadeh et al., 1999; Ioannou et al., 2016; Oehninger & Kruger, 2020; Razavi et al., 2020). Our results suggest that morphometric variables have relevant differences between sire lines; Pietrain boars are estimated to have smaller spermatozoa head sizes with an 82%–85% probability of relevance.…”

Correlations between abnormalities of morphological details and DNA fragmentation in human sperm

“…Sperm morphology is the most relevant parameter in conventional semen analysis for predicting fertilization potential [11,15], a pre- The correlation is significant at the 0.05 level; b) The correlation is significant at the 0.01 level.…”

“…Sperm morphology is the most relevant parameter in conventional semen analysis for predicting fertilization potential [ 11 , 15 ], a prerequisite factor for the successful use of assisted reproductive technology (ART) [ 16 , 17 ]. Our results indicated that abnormal sperm mainly showed changes in head morphology, and that amorphous-head and tapered spermatozoa were more common in the abnormal morphology group.…”

Short Communication: Characteristics of the endangered Javan banteng (Bos javanicus) spermatozoa

“…It means that the design or shape of the head of the spermatozoa, accompanied by force generated by the spermatozoa's tail, will affect the spermatozoa's speed and movement (Nosrati et al 2015;Soulsbury and Humphries 2022). Any abnormalities in spermatozoa morphology will compromise fertility and even cause sterility in males (Cao et al 2017;Feyisa et al 2018;Oehninger and Kruger 2021). The morphology and morphometry of spermatozoa have been studied from various species and showed diversity among species (Villaverde et al 2013;Cursino and Duarte 2016;Yániz et al 2016;Rossi et al 2018;Steinberg et al 2019;Andraszek et al 2020).…”