Canary in a coal mine



Dr Greggory Pinto


IN THE 1900s, British coal miners were exposed to carbon monoxide and other lethal toxic gases. John Scott Haldane and his research on carbon monoxide would in that age provide a solution of using canaries, as early indicators of trouble prompting the miners to evacuate.

A recent study published in human reproductive update has stirred up similar sentiments with regards to the future of mankind. A team of international researchers led by Dr Hagai Levine have shown that the sperm count is declining at an accelerated rate globally. Their meta-analysis looked at 223 studies based on sperm samples from over 57,000 men across 53 countries.

According to the results published last month, globally over the past 5 decades the sperm counts have halved and the rate of decline has more than doubled since the turn of the century. While the sperm count remains an imperfect proxy for fertility, it is closely linked to fertility. Therefore, the substantial and persistent decline should be recognised as a significant public health concern.

Sperm counts are also an indicator of men’s health; with low levels linked to chronic diseases and reduced lifespan. The true canary in the mine. Whilst the study was not designed to provide information on the causes of the declining trend, multiple environmental and lifestyle factors are deemed to play a role, right from the male foetus in the mother’s womb to adult life.


These are chemicals that mimic, block, or interfere with the hormones in the endocrine system of the body. These chemicals may be natural occurring or man-made and formed as by-products during manufacture or combustion of waste or undergo biological/ environmental transformation. Such chemicals now form a wide array of products that we use in the modern day- from pesticides, metals, active ingredients in pharmaceuticals, additives or contaminants in food, personal care products, cosmetics, plastics, textiles, and construction materials.

Notoriously chemicals like Phthalates and bisphenol A (BPA) are used in the manufacturing of everyday use plastics and seep into our food. Most studies have now demonstrated the negative effect these chemicals have on the sperm count. There is mounting concern that in utero exposure to these chemicals to the male foetus can negatively impact various bodily systems, including sperm production.


According to the World Health Organisation (WHO), 39% of men globally are overweight and 11% are obese. Several studies have backed up the negative connection between obesity and low sperm count. Several reasons have been postulated including the release of inflammatory substances that interfere with testosterone production or action and the formation of the sperm is testosterone driven.

A recent study from Italy showed marked improvement in semen parameters in healthy young men, just 4 months after adopting a Mediterranean diet and doing moderate physical activity.


Vaping, tobacco use, marijuana, alcohol, and cocaine, all affect the sperm count and quality of semen. Anabolic steroids are typically used by young men, 20-40 years old who are interested in the performance enhancing effects of steroids. A survey conducted on 10,259 students in secondary schools showed that approximately 3% of the boys use anabolic steroids. Though some of these steroids can be sourced for cheap rates from the internet or local suppliers, they do have major long term side effects including- heart failure, mood and anxiety disorder, infertility directly related to poor sperm production.


According to the WHO more that 1 million STIs are acquired globally on a daily basis. Infections such as Syphilis and Gonorrhoea can cause inflammation, scarring and blockage of the epididymis-a vital structure in the storage of sperm. This results in obstruction and subsequent decline in sperm count in men. Newer evidence shows that Chlamydia trachomatis, Ureaplasma and trichomonas can directly impair sperm production. HIV is known to impact on semen production and sperm counts deteriorate as the disease progresses.


The optimal temperature for sperm production is 2-40 lower than the body temperature, hence the strategic placement where “boys” hang low outside the body. Certain aspects of modern-day living regress this advantage:

• Tight underwear - notorious for turning up testicle heat by bringing it next to the body.

• Tech - laptops and mobile phones emit a considerable amount of heat which are unfortunately placed right over or next to the testicles, jeopardising the low temperature advantage that the little swimmers desperately need to develop.

• Hot saunas and hot baths - though marketed to have several health benefits when it comes to matters fertility and testicular health these are counterproductive.


Infertility is defined as the failure of a couple to achieve pregnancy after more than one year of regular unprotected intercourse. Infertility is not just a female problem as men are just as equally responsible.

In North America about six percent of men suffer from male infertility. One of the common causes of male infertility is a varicocele, which is an abnormal swelling of the testicular vein.

About 40 percent of men with primary infertility and 81 percent of secondary male infertility (previously had a child but currently unable to conceive) have a varicocele. Approximately 15 percent of men in the general population have a varicocele. A varicocele can be corrected by a urologist in a minimally invasive, relatively quick, outpatient procedure.

Other common causes of male infertility are genetic or anatomical abnormalities, previous infections, a prior history of early childhood undescended testes that required surgical correction but occurred after the age of two years old, sperm antibodies, testicular trauma, radiation exposure, hormonal abnormalities, obesity, nicotine smoking and systemic or neurological diseases.

Male infertility can be a complex issue and low sperm numbers is not necessarily the cause or only cause. There are several parameters analyzed in a diagnostic sperm analysis that play important roles in male fertility including total sperm movement/ motility, progressive motility, the shape/ morphology of the sperm, the ejaculate volume, sperm concentration, amongst other important parameters.

One abnormal sperm analysis cannot be used to confirm male infertility, as a repeat sperm analysis should be performed a minimum of three months later.

Modern reproduction assistance technology such as IUI Intrauterine Insemination and IVF In Vitro Fertilisation with or without ICSI Intracytoplasmic Sperm Injection has provided great hope for men with low sperm numbers, poor movement of sperm and low numbers of normally shaped sperm, in allowing them in many cases to achieve viable pregnancies with their partners.

A lot is changing in and around us, the findings of the study by Levine are alarming and perhaps a wake-up call to all of us in matters affecting the male reproductive health. We all have a role to play, small changes will go a long way- changing lifestyle and dietary practices, sexual practices, and our health seeking behaviour.

• Dr Greggory Pinto is a board certified Bahamian Urologist and Laparoscopic Surgeon. Dr. Pinto can be contacted at OakTree Medical Center #2 Fifth Terrace and Mount Royal Avenue, Nassau, Bahamas Telephone: (242) 322- 1145(6)(7) Email: welcome@ urologycarebahamas.com or visit the website:www.urologycarebahamas.com


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