Sperm counts, testicular cancers, and the environmentBMJ 2017; 359 doi: https://doi.org/10.1136/bmj.j4517 (Published 10 October 2017) Cite this as: BMJ 2017;359:j4517
- Niels E Skakkebaek, professor of paediatric endocrinology and andrology
- Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Denmark
A recent meta-analysis by Levine and colleagues1 showing significant declines in sperm counts among men in the Western world caught considerable media attention.2 The Levine study followed a similar report in The BMJ 25 years ago.3 Should we be concerned? Is male reproductive health really at risk?
Meta-analyses have some inherent limitations. However, an important and often overlooked point about data on the quality of semen is that trend data should be interpreted with a holistic view of male reproductive health problems, including parallel trends in testicular germ cell cancer (TGCC). Incidence of this cancer has risen substantially over the past few decades, particularly in young men.4 Increases seem to be occurring even in countries that have had low incidence. TGCC is linked to risk of poor semen quality: reports suggest that countries with a high incidence of …