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The findings of the study of the problem of male sexual health, the most comprehensive for the entire existence of reproductive medicine, clearly indicate that the number of sperm cells in a modern man is decreasing and this is not the best indicator of the health of a man as a whole.
Scientists around the world are already showing serious concern in this regard. And this concern is connected with the rapidly decreasing sperm count in the male half of modern humanity. Until now, no significant research has been carried out to identify the problem, which in fact has become more and more obvious every year.
Recently, the results of a meta-analysis of a large group of scientists from different countries of the world, who coordinated and simultaneously conducted research on various aspects of this problem, were published. The main disappointing conclusion indicates a potential decline in men's health and the associated childbirth.
According to scientists, the number of sperm in men from America, Europe, Australia and New Zealand has fallen by more than 50 percent in less than the last 40 years. The analysis did not reveal any reasons for the decline, but the researchers state that a sharp decrease in the number of spermatozoa is associated with many unfavorable factors, such as exposure to the body of certain chemicals and pesticides, smoking, stress and obesity.
This suggests that sperm quality may reflect the influence of modern life on men's health and act as a “cuckoo on the wall clock”, signaling broader health risks.
Another team of researchers from the USA, Brazil, Denmark, Israel and Spain, led by Professor Hagai Levine from the Jerusalem Medical University, checked and collected the results of 185 semen analyzes for several years of the experiment, and then conducted the so-called meta-regressive analysis.
The results, published in the journal Human Reproduction Update, showed a decrease in sperm concentration of 52.4% and a decrease in the total sperm count in men from North America, Europe, Australia and New Zealand by 59.3%.
The first indicator reflects the concentration of sperm in human ejaculation, while the latter is the concentration of sperm multiplied by the volume.
In contrast, no significant decline was observed in South America, Asia and Africa. However, researchers noted that much less research was conducted in these regions.
Professor Daniel Brison, a specialist in embryology and stem cell biology at the University of Manchester, UK, argues that the results "are of great importance not only for fertility but also for the health of men and the wider public health. ” He also notes that there is still the unanswered question, “will the causes of the decrease in the number of sperm cells affect future generations of children through epigenetic modifications or other mechanisms operating in the sperm?”
Another expert, Professor Richard M. Sharpe from the University of Edinburgh adds: “Given that we still don’t know what lifestyle, dietary or chemical effects could cause such a decrease, research efforts to identify these causes need to be doubled, and the results made predictable.”
Why do the authors of the study declare an emergency in the field of public health in connection with the problem of reducing the total number of spermatozoa and the deterioration of their quality?
Sperm are reproductive cells that are produced in the male gonad, i.e. testicles. Figuratively speaking, an egg is a cauldron that constantly produces sperm. Produced sperm as a good wine must be stored and maintained for 72 days before the sperm are ready to travel.
At the completion of the developmental stage, sperm is released from the testicles through a system of canals that push them out of the penis during ejaculation, along the way the sperm includes enzymes and other necessary ingredients.
When doctors check the quality of sperm using analysis, they pay particular attention to:
an egg that contains at least 15 million sperm per milliliter is more likely to fertilize the egg, i.e. This is a level of fertility concentration that is sufficient for men looking to have children.
In order to reach the seed-conductive paths, the sperm must be fluid, therefore motility is another key condition. A man who has at least 40% of sperm cells is motile is more likely to be conceived.
The form of sperm also matters. If a man is the owner of the sperm of the classical form, his chance of conceiving a healthy baby is definitely high.
The results of sperm analysis on the quality of the same person may differ from the sample by 100% percent, since this is most often determined by the lifestyle of the man. This is especially true of such an indicator as morphology. Habits such as alcohol, tobacco, saunas, etc. Pernicious addiction can significantly change the quality of sperm, so a person's sperm can look very different depending on what he did shortly before conception. The quality of sperm also can not always provide unconditional conception. Scientists have discovered that some men with relatively low sperm count can conceive, while others with more abundant sperm cannot. And it still remains the great mystery of human nature.
Despite a detailed and systematic meta-analysis, there are still a lot of white spots in this extremely serious area of reproductive medicine, because the researchers used only methods known to them that have not changed for years, for example, methods of counting spermatozoa in different conditions and circumstances, using hemocytometer, etc.
But one thing is clear: in the early 1970s, when the research started, men had an average of 99 million sperm per milliliter of sperm. Now that number has dropped to 47 million per milliliter. Thus, every year, the number of male sperm cells decreased by about 1 percent “without any signs of leveling.
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