We know how important the age of the woman is, but there is little talk of the age of the man and they also have their biological clock although the impact is much smaller.
The age of the father can affect their fertility and increases the risk of some diseases in their children. The aging of the reproductive system can manifest itself in three aspects:The volume of the ejaculate is reduced very slowly because the germ vesicles are atrophied. They are the ones that generate the liquid part of the semen.
1. The volume of the ejaculate is reduced very slowly because the seminal vesicles are atrophied. They are the ones that generate the liquid part of the semen.
2. The years can cause oxidation of DNA chains that carry the genetic code and decrease the fertilising capacity of sperm: a DNA chain is like one of those Christmas tree ornaments that are gift packages attached by a cord. In order to fit them in the spermatozoon´s nucleus they roll themselves. This is the so-called “packaging phenomenon”. When they reach the inside of the egg they open to join their 23 packages with the ones from the egg. Well, imagine that you have stored these decorations carelessly and, when you take them out the next Christmas, the cord has broken at several points. This happens in some males by oxidation phenomena: these strings are broken and inside the egg all chromosomes are loose and they do not meet their female counterpart.
We study the degree of DNA fragmentation of a male in a semen sample with the DNA Fragmentation Test. Even if this is high, it is almost always solved with antioxidant pills. We help the testicle be more careful in its packing! In these cases, in In Vitro Fertilisation cycles we use the Fertile chip.
3. Damage to genetic material contained in sperm increases with age and can cause disease in children. We know that, in the phases of cell multiplication there is risk of mutations (at the end of the post I´ll tell you what genetic mutations are). That is, that a pathogenic external agent induces errors in the DNA. This risk is greater the more divisions have been made, in direct relation to the age of the male: During the period of active sex life, the rate of multiplication is approximately 23 per year. Thus, for example, the sperm of a 38 year old man has a history of about 540 divisions and that of a 50 year old man of about 800.
Paternal age over 55 years increases the incidence of diseases such as Klinefelter Syndrome, achondroplastic dwarfism, neurofibromatosis, tuberous sclerosis, Marfan syndrome, Apert syndrome, aniridia and bilateral retinoblastoma; most are rare diseases. Other pathologies such as schizophrenia, bipolar disorder and autism can also occur. Late motherhood and paternity increase the risk of having a child with an autism spectrum: every 5 years, the odds increase by 18%.
Still, the male produces sperm all life and retains its fertility. My friends often say, “Look at that 77-year-old actor who’s having a child with a 40-year-old girl… it probably comes from a sperm bank!” I know it’s the other way around: with his sperm and donor eggs.
What are genetic mutations?
A mutation is a change in the information that a gene carries. People have 23 pairs of chromosomes and each chromosome contains a certain amount of genes. Each gene is responsible for a characteristic of the appearance or functioning of the human organism. For example, there is one gene that determines the skin colour, another the length of hair in each part of the body, etc.
Genetic mutations are necessary changes for the evolution of species and to adapt to the environment. For example, the colour of dark skin in very hot environments
But there are also errors of nature, abnormal mutations can occur in a group of cells and result in a tumour. Or mutations in reproductive cells, which result in the birth of children with inherited diseases
As an example, achondroplasty dwarfism, the mutation affects a gene responsible for growth. It can be inherited, since 50% of children of an affected person will also have the disease, but it can also be a new mutation and a child with dwarfism can be born without having any previous family history.