Lifestyle Factors and Relationships Between Infertility and General Health In Men
The male in an infertile couple should have an initial semen analysis (SA) and male reproductive history evaluation. The reproductive history assessment provides important information about functional sexual, lifestyle and medical history including medications that can contribute to reduced fertility or sterility.
Beyond fertility the semen analysis may also serve as a useful biomarker for overall health and well-being, including the possible diagnosis of testicular cancer, cancer in general, as well as many other medical conditions which may affect sperm motility in the early stages.
A higher mortality rate has been found for infertile men without any specific comorbidity. This assertion has given credence to the assumption that disorders of sperm development may be an indicator of exposure of the male organs to noxious agents within or outside the body.
At least two SAs, ideally obtained at least one month apart, are important to obtain, especially if the first SA has abnormal parameters. The odds ratio for infertility increases as the number of abnormal parameters increases.
Testes produce 200-300 million mature sperm cells daily. However, only about half of these become viable sperm.
Spermatogenesis is the transformation from spermatogonia (the sperm germ cells) to primary spermatocytes, to secondary spermatocytes and spermatids to spermatozoa (mature sperm cells). This process is highly sensitive to fluctuations in the environment, particularly hormones and temperature.
Testosterone is required in large local concentrations to maintain the process. Testosterone is produced by interstitial cells that reside adjacent to the seminiferous tubules.
The seminiferous epithelium is sensitive to elevated temperature and are adversely affected by temperatures as high as normal body temperature. Thus, the testes are located outside the body in the scrotum, and maintain a temperature about two degrees below body temperature.
Dietary deficiencies (such as vitamins B, E and A), anabolic steroids, metals (cadmium and lead), x-ray exposure, dioxin, alcohol, infectious diseases, as well as exposure to pesticides will also adversely affect the rate of spermatogenesis.
Being both underweight or overweight may lead to a low sperm count and infertility. A three-point increase in BMI increases the risk of infertility by 10% in men.
Next month’s article will further discuss lifestyle factors and relationships between infertility and general health in men.