Male infertility, characterized by hypogonadism, decreased semen quality or ejaculatory dysfunction, accounts for approximately 20% of infertility cases. Obesity and metabolic dysfunction have been identified, among other causal factors, to contribute to male infertility. In the context of the Western world's 'obesity epidemic', this article discusses three main biological mechanisms linking obesity to impaired male reproductive function: hypogonadism, testicular heat stress/hypoxia-induced apoptosis and endocrine disruption by 'obesogens'. Among these, obesity-induced hypogonadism is undoubtedly the most clinically significant and is easily assessed. Rapidly expanding areas of research in this area include leptin modulation of kisspeptins and hypothalamic-pituitary-testicular hormone pathways, and roles of other adipocytokines in male infertility, as well as the impact of exposure to obesogens on the quality of semen.
Expert review of endocrinology & metabolism. 2010 Mar [Epub]
Karen P Phillips, Nongnuj Tanphaichitr
a Assistant Professor, Interdisciplinary School of Health Sciences, Faculty of Health Sciences, Principal Scientist, Institute of Population Health, University of Ottawa, 43 Templeton Street, Room 215, Ottawa, ON K1N 6N5, Canada. ., b Senior Scientist, Ottawa Hospital Research Institute, and Professor in Obstetrics and Gynecology, and Biochemistry/Microbiology/Immunology, University of Ottawa, 725 Parkdale Avenue, Ottawa, ON K1Y 4E9, Canada. .