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
Over the last 50 years, a marked decrease in sperm count has been observed in the western world. But what about the situation in Switzerland? Up until now, no study had evaluated the reproductive health of Swiss young men. Researchers from the University of Geneva (UNIGE), Switzerland, working in collaboration with other institutions and with logistical support from the Swiss army, have undertaken the first nationwide assessment of the semen quality of men between the age of 18 and 22.
The scientists assessed three important parameters: the number of spermatozoa, their motility and morphology. The results were well below the reference values issued by the World Health Organisation (WHO). The current situation is a matter of concern, since the poor semen quality of Swiss men is associated with an increase in the incidence of testicular cancer. You can read about the study in the journal Andrology.
Numerous epidemiological studies in industrialized countries over the past decades have shown a drop in semen quality with a particular decrease in the sperm concentration from 99 million per milliliter (ml) to 47 million per ml. "It's important to understand that the time needed to conceive increase significantly if a man has a sperm concentration below 40 million sperm per ml," explains Serge Nef, professor in the Department of Genetic Medicine and Development in UNIGE's Faculty of Medicine. A man whose sperm concentration is below 15 million per ml can be considered subfertile and is more likely to encounter problems conceiving a child, regardless of the fertility of his partner. Infertility is defined as the inability to conceive after 12 months of regular unprotected sexual intercourse.
The UNIGE researchers conducted the first national study on the quality of Swiss sperm by analyzing the profile of 2,523 young men aged 18 to 22 as part of their military recruitment. The men came from every canton in Switzerland and were conceived and born in the country. They completed a questionnaire about their health, lifestyle, diet and education. In addition, their parents filled in a questionnaire about their own lifestyle, diet, health and the course of the pregnancy. This was designed to assess the conditions under which gestation took place and to evaluate the possible impact on the reproductive health of the young men. Semen quality is defined by three important parameters: the sperm concentration (number of sperm per ml), their motility and morphology.
Sperm counts vary from one country to another, with median concentrations ranging between 41 to 67 million per ml for young European men. By way of comparison, Swiss men with 47 million per ml are at the bottom of the pack alongside Denmark, Norway and Germany.
Based on the WHO thresholds established in 2010, the results of the study indicate that 17 percent of young men had a sperm concentration below 15 million per ml and 25 percent had less than 40 percent motile spermatozoa in their ejaculate. The rate of morphologically normal forms was below 4 percent in 40 percent of the subjects. The study as a whole revealed that at least one of the three parameters (concentration, motility and morphology) was below the WHO thresholds for 60 percent of men, and that 5 percent had a problem concerning these three factors at the same time.
The study did not identify differences in sperm quality between Switzerland's various geographical regions, linguistic areas, as a proxy for different lifestyle factors. There was also no differences between urban or rural regions. However, maternal smoking during pregnancy was found to be associated with a decrease in sperm quality, as professor Nef adds: "Subfertility was found to be more common among men who were exposed to maternal smoking during embryonic development."
Is there a link between sperm quality and testicular cancer? The Geneva-based researchers also used the study to identify a correlation between poor semen quality and increased testicular cancer in Switzerland. "For 35 years, testicular cancer has grown steadily to over 10 cases per 100,000 men, which is very high compared to other European countries. Sperm quality is generally lower in countries where the incidence of testicular cancer is high," says professor Nef. This is almost certainly the result of altered testicular development at the fetal stage, prompting the scientists to further investigate this area.