Semen quality of young men in Switzerland: a nationwide cross‐sectional population‐based study

R. Rahban, L. Priskorn, A. Senn, E. Stettler, F. Galli, J. Vargas, M. Van den Bergh, A. Fusconi, R. Garlantezec, T. K. Jensen, L. Multigner, N. E. Skakkebæk, M. Germond, N. Jørgensen, S. Nef

Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland; Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Swiss Armed Forces Joint Staff, Medical Services, Ittigen, Switzerland; National Institute for Cancer Epidemiology and Registration (NICER), Zurich, Switzerland; Centre de Procreation Medicalement Assist ee SA, Fertas SA et Fondation FA BER, Lausanne, Switzerland; Kinderwunschzentrum, Kantonspital Baden, Baden, Switzerland; Centro Cantonale di Fertilita, Ospedale di Locarno La Carita, Locarno, Switzerland;  and Inserm, EHESP, Irset (Institut de recherche en sante, environnement et travail) – UMR_S 1085, Universite de Rennes, Rennes, France

Abstract: 

Background: Sperm counts have been steadily decreasing over the past five decades with regional differences in the Western world. The reasons behind these trends are complex, but numerous insights indicate that environmental and lifestyle factors are important players.
Objective: To evaluate semen quality and male reproductive health in Switzerland.
Materials and methods: A nationwide cross‐sectional study was conducted on 2523 young men coming from all regions of Switzerland, recruited during military conscription. Semen volume, sperm concentration, motility, and morphology were analyzed. Anatomy of the genital area and testicular volume was recorded. Testicular cancer incidence rates in the general population were retrieved from Swiss regional registries.
Results: Median sperm concentration adjusted for period of sexual abstinence was 48 million/mL. Comparing with the 5th percentile of the WHO reference values for fertile men, 17% of men had sperm concentration below 15 million/mL, 25% had less than 40% motile spermatozoa, and 43% had less than 4% normal forms. Disparities in semen quality among geographic regions, urbanization rates, and linguistic areas were limited. A larger proportion of men with poor semen quality had been exposed in utero to maternal smoking. Furthermore, testicular cancer incidence rates in the Swiss general population increased significantly between 1980 and 2014.
Discussion: For the first time, a systematic sampling among young men has confirmed that semen quality is affected on a national level. The median sperm concentration measured is among the lowest observed in Europe. No specific geographical differences could be identified. Further studies are needed to determine to what extent the fertility of Swiss men is compromised and to evaluate the impact of environmental and lifestyle factors.
Conclusion: A significant proportion of Swiss young men display suboptimal semen quality with only 38% having sperm concentration, motility, and morphology values that met WHO semen reference criteria.

Full article here

ANDROLOGY – https://doi.org/10.1111/andr.12645
First published: 21 May 2019