The Metabolic Syndrome and Male Infertility: A Review of the Literature

Abstract

The Metabolic Syndrome (MetS) is a constellation of various risk factors, including obesity, dyslipidemia, hypertension, and impaired glucose metabolism, with insulin resistance as the hypothesized underlying pathogenic mechanism. In recent years, the Metabolic Syndrome (MetS) is note worthy due to its association with the development of cardiovascular disease and type 2 diabetes mellitus. According to the American Heart Association, 47 million Americans have MetS. The numerous deleterious effects of MetS are being investigated throughout the medical community, as MetS may potentially affect many aspects of human physiology due to its systemic nature. The impaired glucose metabolism is widely accepted as a negative effecting factor on human fertility in either gender. Obesity appears to be associated with male reproductive dysfunction and infertility. Elevated Free Fatty Acids (FFAs), associated with dyslipidemia in MetS, can cause endothelial dysfunction through increased free radical production and inhibition of NO synthesis.Infertility, defined as the inability to conceive after one year of unprotected intercourse, affects approximately 15% of couples. Male factor infertility is the sole cause of infertility in approximately 20% of infertile couples, with an additional 30% to 40% secondary to both male and female factors. Thus, male factor infertility is present in approximately half of all infertile couples. Recently in some studies, it has been reported that increased body mass index negatively affects on male fertility or semen parameters. This review will evaluate MetS and its components in order to establish a paradigm with male factor infertility.