Currently, studies of the effect of outdoor air pollution on male fertility factors such as semen quality, DNA fragmentation and sperm morphology are not conclusive. A paper entitled “Outdoor Air Pollution and Sperm Quality” by Lafuente, Garcia-Blàquez, Jacquemin and Checa in the September issue of Fertility and Sterility is a systemic review of the papers that assessed the impact of air pollutants on sperm quality.
The authors conducted an exhaustive search of three databases: PubMed, ISI Web of Knowledge and the Cochrane Library through June 30, 2016. After careful evaluation, they included 17 studies in their analysis. The studies were conducted in a number of countries including Poland, Czech Republic, Turkey, Italy, USA and China. The authors used the Newcastle-Ottawa Scale to access the risk of biases of the study in three categories: selection, comparability and outcome.
Of the 17 articles, 13 assessed environmentally measured exposure to air pollution and 6 articles measured air pollution exposure with biomarkers. Only 2 articles used both measurements. The authors were not able to perform a meta-analysis since there was considerable diversity of air pollution measures, sperm quality outcomes and the techniques used to study these parameters. They did find some evidence of an impact of outdoor air pollution on semen quality parameters, especially DNA fragmentation and sperm morphology. They conclude that pollutants of outdoor air may have a possible impact on male fertility. Therefore, they call for further studies and for the standardization of research techniques in the study of this aspect of male sperm health.
Male factor infertility has increased in the past several decades and is now considered to be approximately 40% of all infertility cases. A decline in even fertile men in semen quality, sperm count, sperm concentration, sperm morphology and ejaculate volume has been observed over the past 70 years world-wide. In view of these facts, it is the position of The Campion Fund that there is a pressing need for well-designed studies to be conducted now.