Medical records documenting male fertility since the early 1900’s have shown a steady fall in male fertility. Coinciding with this trend has been a significant decline in sperm count. A reduction in sperm concentration can make fertilization very difficult, leading to a lower birth rate. Presently, low sperm count is the leading cause of male subfertility. This raises the question, what are men doing so differently now compared to a century ago that has lead to lower sperm counts?
About the three causes of low sperm count in men: lifestyle, genetic & medical and environmental
Causes of Low Sperm Count
There are a wide range of factors that can influence sperm count. Some are easy to identify and remedy, while others are more serious and difficult to resolve. Lifestyle choices, genetics, medical conditions, and environmental factors all influence sperm count.
Thus, sperm count naturally varies throughout a male’s life. It’s when prolonged periods of low sperm count occur that subfertility issues arise.
Temporary reductions in sperm concentration can be easily triggered by mental and/or physical stress. Studies have shown that emotional stress can interfere with the production of gonadotropin-releasing hormone (GnRH), leading to a reduction in sperm count1.
Overheating can also lower sperm count temporarily, such as high fevers or spending too much time in saunas.
Substance abuse can have a major impact on sperm count. Studies have shown that users of cocaine2 and marijuana3 exhibit significantly lower sperm counts. Abuse of legal drugs such as alcohol4 and tobacco5 also results in poor sperm concentration. In most instances, resisting these drugs can help to improve sperm count.
Diet has a major influence on the quality and quantity of sperm. Malnutrition and nutrient deficiencies can seriously impede fertility. Various amino acids, vitamins, minerals and trace elements are essential for a healthy body and thus, healthy fertility. Paying particular attention to diet can assist in elevating sperm count, enhance mobility and sperm morphology.
Several studies have found a link between subfertility and obesity. Men who are overweight tend to have low sperm motility and low sperm concentration. Obese men in particular have a much lower sperm count6. Several mechanisms are attributed to the higher rate of subfertility in overweight men, including changes in hormonal profiles, sleep apnea, and increased scrotal temperatures.
Genetics and medical factors
There are certain genetic disorders and medical conditions that can impair fertility. Cystic fibrosis and Kartagener syndrome both cause low sperm counts and other fertility issues.
Structural abnormalities associated with the tubes that transport sperm will also lead to low semen levels and poor sperm count. Infections, antibodies, hormonal imbalances, undescended testicles, and certain medications can all negatively impact sperm concentration, reducing fertility.
Each day the body is exposed to a wide array of toxins that can decrease sperm count. This may occur as a result of direct effects on hormone systems and testicular function, although isolating specific cause and effect is challenging and somewhat controversial.
Some chemicals that are known to affect the production of sperm include pesticides such as aldrin, DDT, PCPs, dielfrin, furans and dioxins7; plastic derived compounds such as benzene, ethylbenzene, xylene, BPA and toluene8.
Long-term studies into the effects of prolonged and cumulative chemical exposure on male fertility are largely absent. Thus, the true extent of the effects of synthetic toxins on sperm count is currently unknown.
Over exposure to heavy metals such as arsenic, cadmium and lead can cause a decline in sperm production9 10. These metals inhibit enzyme function within sperm, decreasing fertility. X-rays and radiation treatment can also damage sperm production.
There is a reduced risk of recovery when exposed to significant radiation levels, making recovery time dose dependant11.
We live in a high-pressure society, where physical and emotional stresses are prevalent. Healthy diets are substituted for convenience foods and sedentary lifestyles are becoming more prevalent. While some causes of subfertility are difficult to control, such as hereditary and environmental influences, lifestyle choices can be modified.
Eating a balanced diet, maintain a healthy body weight and avoiding various drugs can help to enhance fertility.
- Wagenmaker ER, Breen KM, Oakley AE, Tilbrook AJ, Karsch FJ. Psychosocial Stress Inhibits Amplitude of Gonadotropin-Releasing Hormone Pulses Independent of Cortisol Action on the Type II Glucocorticoid Receptor. Endocrinology. 2009. 150(2): 762-9 ↩
- Bracken MB, Eskenazi B, Sachse K, McSharry JE, Hellenbrand K, Leo-Summers L. Association of Cocaine Use With Sperm Concentration, Motility, and Morphology. Fertility and Sterility. 1990. 53(2): 315-22 ↩
- Close CE, Roberts PL, Berger RE. Cigarettes, Alcohol and Marijuana Are Related to Pyospermia in Infertile Men. Journal of Urology. 1990. 144(4): 900-3 ↩
- Gomathi C, Balasubramanian K, Bhanu NV, Srikanth V, Govindarajulu P. Effect of Chronic Alcoholism on Semen-Studies on Lipid Profiles. International Journal of Andrology. 1993. 16(3): 175-81 ↩
- Künzle R, Mueller MD, Hänggi W, Birkhäuser MH, Drescher H, Bersinger NA. Semen Quality of Male Smokers and Nonsmokers in Infertile Couples. Fertility and Sterility. 2003. 79(2): 287-91 ↩
- Hammoud AO, Wilde N, Gibson M, Parks A, Carrell DT, Meikle AW. Male Obesity and Alteration in Sperm Parameters. Fertility and Sterility. 2008. 90(6): 2222-5 ↩
- Wong WY, Zielhuis GA, Thomas CMG, Merkus HMWM, Steegers-Theunissen RPM. New Evidence of the Influence of Exogenous and Endogenous Factors on Sperm Count in Man. European Journal of Obstetrics, Gynaecology and Reproductive Biology. 2003. 110(1): 49-54 ↩
- Talsness CE, Andrade AJM, Kuriyama SN, Taylor JA, Vom Saal FS. Components of Plastic: Experimental Studies in Animals and Relevance for Human Health. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. 2009. 364(1526): 2079-96 ↩
- Xu B, Chia SE, Tsakok M, Ong CN. Trace Elements in Blood and Seminal Plasma and Their Relationship to Sperm Quality. Reproductive Toxicology. 1993. 7(6): 613-8 ↩
- Sinclair S. Male Infertility: Nutritional and Environmental Considerations. Alternative Medicine Review. 2000. 5(1): 28-38 ↩
- Howell SJ, Shalet SM. Spermatogenesis After Cancer Treatment: Damage and Recovery. Journal of the National Cancer Institute. 2005. (34): 12-7 ↩