They slow down, diminish, lose vigor. At the test of Covid, male spermatozoa can go into suffering and struggle to reach the goal, the egg to be fertilized. In the last period, marked by the growth in the number of infections among young people, the questions about the risks for male fertility multiply. To dispel some doubts is a study published in the journal Reproduction, Fertility and Development, according to which the negative impact of Covid on spermatozoa would be only temporary.
International researchers, under the aegis of Mashhad University and Shahid Beheshti University of Medical Sciences, in Iran, found reduced sperm motility in about twenty men who had fallen ill with Covid in moderate form two weeks earlier. Within four months, however, the values had returned to normal, as were most of the other indicators examined for semen quality.
“It is plausible that these alterations are transitory and within 3-4 months there is a normalization in the healed, due to the reduction of the inflammatory response and the production of new spermatozoa”, confirms Rocco Rago, director of the Reproductive Physiopathology and Andrology Unit of the Sandro Pertini hospital in Rome. These are promising data but to be consolidated on larger numbers, “overcoming an intrinsic limit, that linked to the absence of information on seminal parameters before infection”. The decline of male fertility, in fact, is a phenomenon that has been observed for years on a global level, well before the arrival of Sars-CoV-2.
That this virus can affect the reproductive sphere of men, however, is more than an intuition, because in the last year and a half it has been understood that the testicles are particularly exposed to the Coronavirus (much more than the ovaries in women), because they express in markedly a receptor – called ACE2 – with which the virus binds to infect cells.
“It is not surprising that Covid at the level of the male reproductive system behaves like other infectious diseases, in particular viral – explains Rago – In fact, over 30 viruses are known, from mumps to HIV, from hepatitis to Zika, capable of spreading in sperm and causing various complications affecting the genitals and fertility “.
The “culprit” of the damage is above all the inflammation triggered by our immune system after the encounter with the virus, which in the testicles causes damage to the cells that generate sperm and those that produce testosterone, as well as causing oxidative stress. It is no coincidence that the typical question that is asked before the examination of the seminal fluid is if you have had a fever, because precisely the rise in temperature, mediated by inflammation, even for a trivial influence can alter its values.
The consequences can be a reduction in sperm volume and sperm count, as well as in their perfection and motility: a problem that is estimated to affect a quarter of men recovered from Sars-CoV-2 infection.
What happens, however, in children and adolescents whose reproductive system is maturing? “The one on Covid and fertility in the very young is a question mark, because at the moment it is difficult to evaluate its biological effects in the long term, as there are many variables at stake”, highlights Maria Chiara Lucchetti of the Andrological Surgery team of the Bambino Gesù pediatric hospital in Rome. So far, a single study has been published, referring to the case of a 14-year-old with orchiepididymitis (an inflammation of the epididymis and testicles) following Covid. “It should be considered if you get sick as a child or adolescent, since the prepubertal reproductive system is different from puberty. Younger people may be more vulnerable because the younger the age, the higher the representation of the ACE2 receptors through which Sars-CoV-2 enters the cells – he continues – From the point of view of fertility, however, in children, since the production of spermatozoa has not started, which are still in the state of inactive dormant cells, it is conceivable that no harm will occur to those who contract. the virus. Among the other factors that can have an influence there are also the therapies taken to counteract the Sars-CoV-2 infection, as well as the effect of hormones, with a possible protective action “.
Question marks contrasted by a crystalline certainty: the vaccine, protecting from the disease and its possible consequences, remains one of the key safeguards for taking care of reproductive health as well. This is confirmed by a study published in the journal Jama, conducted on 45 adult volunteers evaluated before and after the administration of the mRna vaccine, from which it emerges not only that the quality of the seminal fluid does not change, but that in some cases after the second dose the sperm value, motility and concentration increase spermatozoa.
“On the anti-Covid vaccine even in teenagers there is no reason, not even theoretical, to hypothesize harmful effects on reproductive capacity: we know this for sure – remarks Lucchetti – The invitation to hesitant parents is to consider that, by choosing to vaccinate their own child, perhaps indirectly they are also protecting her future fertility. “
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