Semen variation in a population of fertile donors: evaluation in a French centre over a 34‐year period

Abstract

Although it has been suspected that there is a decrease in semen quality over time, the results reported to date remain debatable because of methodological issues. The aim of the study reported here was to investigate the evolution of semen quality over time in a population of 1114 fertile candidates for sperm donation at CECOS, Tours, between 1976 and 2009. We investigated semen volume, sperm concentration, progressive motility, vitality, percentage of normal forms and multiple abnormalities index of the first ejaculate in this population. We did not find a decline in semen volume, whereas we observed a significant decrease in total sperm count (from 443.2 million in 1976 to 300.2 million in 2009), motility (from 64% in 1976 to 49% in 2009) and vitality (from 88% to 80%). Moreover, a significant decline in the percentage of normal forms was noted between 1976 and 1997 (from 67% to 26%) with a steady rise in the multiple abnormalities index between 1998 and 2009 (from 1.19 to 1.65). This study involving a population of fertile men from a restricted area revealed various degrees of decline in semen parameters over a period of 34 years. These findings will have to be compared with findings in other geographical areas.

Decline in sperm count and motility in young adult men from 2003 to 2013: observations from a U.S. sperm bank

“…Splingart et al . () reported a significant decrease in total sperm count, motility, viability and normal forms in Tours, France from 1976 to 2009. Similarly, Rolland et al .…”

The quality of semen among a sample of young, healthy men from Lower Silesia (AndroLS)

“…The high percentage of reduced-quality semen together with the increasing age at which women decide to get pregnant may explain the reduced fecundity of populations from several countries [32,35]. In fact, the decline in sperm counts in recent decades has been reported in numerous studies [3,36], although not all authors have observed this trend [5,37]. If the trend is real, the ageing process could be accelerated at the level of whole populations, which would create serious medical as well as socio-cultural threats to many societies (especially in ageing Europe).…”

“…There is an ongoing discussion regarding the decline of the number and quality of spermatozoa in humans [1][2][3]. This phenomenon is of special importance in the context of worrisome demographic trends in developed countries and because male factors may play a role in 40% of infertile couples [4].…”

Paternal lifestyle factors in relation to semen quality and in vitro reproductive outcomes

“…According to two meta‐analyses, seminal parameters, which are predictors of male fertility potential, have been declining over time worldwide (Carlsen, Giwercman, Keiding, & Skakkebaek, ; Swan & Elkin, ), and recent studies have corroborated this finding (Borges, Setti, Braga, Figueira Rde, & Iaconelli, ; Fernandez et al, ; Sengupta, Dutta, & Krajewska‐Kulak, ; Splingart et al, ). This decline in semen quality is likely multifactorial, and a variety of lifestyle factors have been proposed to influence spermatogenesis and reproductive function, either positively (Gaskins, Colaci, Mendiola, Swan, & Chavarro, ; Minguez‐Alarcon et al, ) or negatively (Braga et al, ; Gaskins et al, ; Joo, Kwon, Myung, & Kim, ; Silva et al, ).…”