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Two years ago scientists reported an alarming and steep decline in sperm counts in men from Western industrialized countries over the last 40 years. Both sperm count and sperm concentration declined 50 to 60% in this period in men in North America, Europe, Australia, and New Zealand. Especially concerning was that there was no evidence of this year by year decline leveling off.

What does this mean? As these declines continue, more and more men will have sperm counts below the point at which they can reproduce. Instead they will be infertile or "sub-fertile" (fertilization is unlikely). According to the World Health Organization (WHO), a sperm count of below 15 million per ml makes a man subfertile. However, also of concern is the threshold level associated with a "decreased monthly probability of conception", which is 40 million/ml - which means conception will take significantly longer (due to impaired ability to fertilize an egg).

A recent Univ. of Geneva study looked at semen quality of 2523 young men (aged 18 to 22 years old) who were being drafted into the military in Switzerland. They found that average sperm quality and sperm concentration of the men, who were from all regions of Switzerland, was among the lowest in Europe (along with Germany, Denmark, and Norway).

In Europe, median sperm count ranges from 41 to 67 million per milliliter (ml), depending on the country. The researchers found that the group of Swiss men had a median sperm count of 48 million per ml. And 17 percent of the men had sperm counts below 15 million per ml (thus subfertile). By the way, countries with lower sperm counts and quality, have higher rates of testicular cancer - they go hand in hand.

Also, in a quarter of the Swiss men studied, less than 40 percent of sperm cells were motile (moved normally), and 43 percent of men had less than 4 percent normally formed sperm. Overall, only 38 percent of Swiss men had healthy sperm - that is, with concentration, motility, and morphology (shape, form) that met the WHO’s criteria for healthy sperm.

Why is this happening? The researchers found that of the men with very low sperm concentration, more of their mothers smoked during the pregnancy, which means there could be changes during embryonic development. Also, while this study did not discuss this, many other researchers say that sperm health is "the canary in the mine" for male health - evidence of harm to men from environmental and lifestyle influences. 

These Western developed countries are awash in chemicals and plastics, also with endocrine disruptors (hormone disruptors) in our foods, our personal care products, in products all around us - and so studies find these chemicals in all of us (in varying degrees). Same with flame retardants, pesticides, "scented" products. Exposure to all sorts of environmental pollutants - whether in air, water, soil, our food - such as high levels of aluminum. All of these can have an effect on sperm counts and reproductive health. You can't totally avoid these chemicals, but you can try to lower your amounts of exposure (some tips to lower exposures).

From Medical Xpress: Poor semen quality in Switzerland   ...continue reading "Male Fertility Is Plunging In Switzerland"

To the alarm of many, male fertility (sperm quality and sperm counts) has been rapidly declining over the past few decades. Researchers suspect that it's due to our exposure to chemicals in the environment, especially to endocrine disrupting chemicals - of which there are many, and to which we are exposed to daily. A recent study found that detrimental effects occur in the sperm of both humans and dogs when exposed to the common plastic softener DEHP and the persistent industrial chemical polychlorinated biphenyl 153 (PCB153). The researchers suggest this is because dogs live in households with humans and thus are exposed to the same environmental contaminants.

DEHP (diethylhexyl phthalate) is an endocrine disruptor (interferes with hormone systems) that is found in plastic materials in many household and personal items - for example, in carpets, vinyl flooring, some upholstery, rainwear, wires, some plastic toys, fragrances and air fresheners, some PVC pipes, some food packaging, medical tubing, plastic shower curtains. The problem is that it slowly leaches out of the products and into the air and household dust, it leaches out of packaging into foods (which we then ingest), and it can also be absorbed through direct skin contact. Bottom line: try to avoid DEHP by avoiding plastics known as polyvinyl chloride (PVC) or vinyl as much as possible. (One can't totally avoid them, but can reduce exposure to them.)

From Science Daily: Chemical pollutants in the home degrade fertility in both men and dogs, study finds

New research by scientists at the University of Nottingham suggests that environmental contaminants found in the home and diet have the same adverse effects on male fertility in both humans and in domestic dogs.  ...continue reading "Common Chemical Has Negative Effects On Sperm of Both Humans and Dogs"

Air pollution is linked to so many negative health effects, now another one - poorer quality sperm. In this study 6475 males  (ages ranged from 15–49 years) had their sperm analyzed as part of a standard medical examination program in Taiwan. They were also able to get air pollution measurements for each person's address for that time period. They found that both short-term and long-term exposure to higher levels of fine particulate matter (PM2.5) pollution were linked to lower numbers of sperm being normal in size and shape (sperm morphology), but with a higher concentration of sperm. Perhaps a  compensatory phenomenon?

The researchers pointed out that other studies have also found effects from air pollution on sperm. Since this study only analyzed a person's sperm one time, the findings are correlational (they observed an association, but couldn't definitely say it caused the effect). [Some other posts on sperm qualityhere, here, here.] From Medical Xpress:

Air pollution linked to poorer quality sperm

Air pollution, particularly levels of fine particulate matter (PM2.5), is associated with poorer quality sperm, suggests research published online in Occupational & Environmental Medicine. Although the size of the effect is relatively small in clinical terms, given how widespread air pollution is, this might spell infertility for a "significant number of couples," say the researchers.

Environmental exposure to chemicals is thought to be a potential factor in worsening sperm quality, but the jury is still out on whether air pollution might also have a role. To explore this possibility further, the international team of researchers looked at the impact on health of short and long term exposure to fine particulate matter (PM2.5) among nearly 6500 15 to 49 year old men in Taiwan.

The men were all taking part in a standard medical examination programme between 2001 and 2014, during which their sperm quality was assessed (total numbers, shape/size, movement) as set out by World Health Organization guidelines. PM2.5 levels were estimated for each man's home address for a period of three months, as that is how long it takes for sperm to be generated, and for an average of 2 years, using a new mathematical approach combined with NASA satellite data.

A strong association between PM2.5 exposure and abnormal sperm shape was found. Every 5 ug/m3 increase in fine particulate matter across the 2 year average was associated with a significant drop in normal sperm shape/size of 1.29 per cent. And it was associated with a 26 per cent heightened risk of being in the bottom 10 per cent of normal sperm size and shape, after taking account of potentially influential factors, such as smoking and drinking, age or overweight. However, it was also associated with a significant increase in sperm numbers, possibly as a compensatory mechanism to combat the detrimental effects on shape and size, suggest the researchers. Similar findings were evident after three months of exposure to PM2.5. [Original study.]