Male Infertility is a Women’s Health Issue—Research and Clinical Evaluation of Male Infertility Is Needed

Abstract

Infertility is a devastating experience for both partners as they try to conceive. Historically, when a couple could not conceive, the woman has carried the stigma of infertility; however, men and women are just as likely to contribute to the couple's infertility. With the development of assisted reproductive technology (ART), the treatment burden for male and unexplained infertility has fallen mainly on women. Equalizing this burden requires reviving research on male infertility to both improve treatment options and enable natural conception. Despite many scientific efforts, infertility in men due to sperm dysfunction is mainly diagnosed by a semen analysis. The semen analysis is limited as it only examines general sperm properties such as concentration, motility, and morphology. A diagnosis of male infertility rarely includes an assessment of internal sperm components such as DNA, which is well documented to have an impact on infertility, or other components such as RNA and centrioles, which are beginning to be adopted. Assessment of these components is not typically included in current diagnostic testing because available treatments are limited. Recent research has expanded our understanding of sperm biology and suggests that these components may also contribute to the failure to achieve pregnancy. Understanding the sperm's internal components, and how they contribute to male infertility, would provide avenues for new therapies that are based on treating men directly for male infertility, which may enable less invasive treatments and even natural conception.

IVF, from the past to the future: the inheritance of the Capri Workshop Group

“…The fact that sperm carry more than a genome and centrosome has added more complexity to this process, especially since sperm factors other than DNA in animal studies indicate their role in the later stages of embryonic development. Among these factors are various species of RNA molecules that are acquired by sperm either in the testis or while transiting through the epididymis ( Sharma et al , 2016 ; Burl et al , 2018 ; Turner et al , 2020 ). These RNAs are delivered to the oocyte at the time of fertilization, and appear to be directly involved with remodeling of the embryos maternal and paternal contributions to the newly formed zygote.…”

“…These RNAs are delivered to the oocyte at the time of fertilization, and appear to be directly involved with remodeling of the embryos maternal and paternal contributions to the newly formed zygote. Given that even normospermic ejaculates exhibit heterogeneity in sperm with respect to motility, degree of DNA fragmentation, and acrosome integrity, characterizing both the source and function of these sperm RNAs has become a future research priority in the area of sperm selection ( Turner et al , 2020 ).…”

Essential role of CFAP53 in sperm flagellum biogenesis

“…S. Lehti & A. Sironen, 2017). Defects in formation of the flagellum disrupt sperm morphology and motility, leading to male infertility (Chemes & Rawe, 2010; Sironen et al, 2020; Turner et al, 2020). Great progress has been made in our understanding of the pathogenesis of flagella-related diseases in recent years, but the pathogenic genes and mechanisms of flagellum biogenesis are far from being fully understood.…”

Evaluation of the association between polymorphisms of PRM1 and PRM2 and the risk of male infertility: a systematic review, meta-analysis, and meta-regression

“…Male factor infertility affects up to 50% of couples' infertility and accounts for only 20% of total infertility 2 . Recently, however, the male factor infertility incidence has increased 3 , 4 . Male infertility is currently assessed through routine analysis according to sperm concentration/number, motility, and sperm morphology.…”

“…Inclusion and exclusion criteria. The inclusion criteria included (1) study focus on PRM1 polymorphisms rs35576928, rs737008, rs35262993, rs2301365, rs140477029, and rs193922261 and also PRM2 polymorphisms of rs1646022, rs779337774, rs545828790, rs201933708, rs115686767, rs200072135, and rs2070923 with male infertility susceptibility; (2) case-control studies on human beings that the cases were infertile patients with idiopathic infertility and including all subtypes (mainly azoospermia, cryptozoospermia, and oligozoospermia) and the controls were fertile; (3) including the details of genotype or allele frequency of cases and controls; (4) studies with complete full-text, and (5) studies with every language, (6) studies with or without deviation from the Hardy-Weinberg equilibrium (HWE) in controls. The exclusion criteria included (1) studies not concerning the association between PRM polymorphisms mentioned above and male infertility susceptibility; (2) animal articles, review studies, meta-analyses, and conference papers or editorial articles; (3) duplicate studies; and (4) studies with irrelevant data.…”