The maturation of sperm takes about 2 months, after which they remain active for about a month while in the male body. If ejaculation does not occur, the body “utilizes” the sperm, and the next one takes their place. With very frequent sexual intercourse, sperm fertility decreases sharply. It actually contains only seminal fluid, and the percentage of sperm is extremely small.

How long do sperm live in the vagina?

The acidic environment of the vagina is harmful to sperm. This makes them move more actively, and the strongest, most active and tenacious sperm gets to the egg. The purpose of seminal fluid is to protect the sperm, and therefore the likelihood that a sperm that gets into the vagina from underwear will survive is zero.

In the vagina, sperm will remain active for about 2 hours; if a woman has diseases that shift the pH of the vagina to an even more acidic side, the life of the sperm is significantly shortened. When there is a shift to the alkaline side, which often happens with STDs, sperm do not die longer, but they practically do not move towards the cervical canal. Some experts believe that the alkaline environment of the vagina allows sperm to fertilize an egg that would not normally be capable of this. This leads to worse performance in the offspring.

Lifespan of sperm in the fallopian tubes

In the fallopian tubes, sperm can remain active for 6-7 days. But it has been noticed that X sperm move slower and live longer, while Y sperm are very active, but their life cycle is much shorter. This allows you to maintain balance and give equal chances of birth to girls and boys. So, if sexual intercourse occurred on the day or on the eve of ovulation, then most often, and if intercourse took place several days before ovulation, then the likelihood of having a girl will be higher ─ slow X-sperm manage to travel to the egg and successfully fertilize it. This is the basis of the method of physiological contraception ─ 7 days before ovulation are considered potentially dangerous.

High temperatures are detrimental to genetic material. If a woman has a high body temperature, then most likely most of the sperm will die. Excessive heat also harms men. It has been noticed that those who work in hot shops often visit saunas and steam baths, sperm activity is reduced, and their life cycle is very short.

In the external environment, provided there is sufficient humidity, sperm can live for 2-3 hours. This is precisely what is associated with the risk of pregnancy during repeated unprotected sexual intercourse. And, although the risks are minimal, it is worth taking a shower or using special wipes for genital hygiene.

Men can be just as curious as women. Therefore, some of them are very interested in the structure of their own body, and especially its most important organs. In this case, the brave ones become doctors, and the rest simply read the necessary literature. The most important questions remain: Where is the sperm formed? What does he look like? How long does he live? And how does it move? Let's try to answer them in a way that everyone can understand.

Definition

Before answering the question of where sperm is formed, you need to understand what it is. Sperm are the reproductive cells of animals and humans. As a rule, these cells are able to actively move, which is vital in order to reach the egg and fertilize it.

Compared to the female reproductive cell, sperm are small, nimble, and a large number of them mature in the body at the same time (unlike the egg, which alone is the crown of the thirty-day work of a woman’s endocrine system).

The structure of this reproductive cell indicates that all animals and fungi had a common ancestor - a single-celled organism. Traditionally, any male reproductive cells, even in plants, are called spermatozoa, although the definition of “sperm” is also applicable to them, as well as antherozoids.

Sperm in animals

Oddly enough, animals are not very different from humans in the structure and function of germ cells. Where are sperm produced? What do they look like? Are there any fundamental changes?

An ordinary animal sperm has a head, an intermediate part and a tail (or flagellum). The head, traditionally, contains the nucleus, which contains half the set of chromosomes. In addition to genetic information, the head contains enzymes for penetration into the egg and centriole. In the intermediate part, also known as the neck, there is a large mitochondrion, which provides energy to the flagellum and supports its movement.

Exceptions to the sample presented above are some types of aquarium fish, whose sperm have two flagella. This also applies to crustaceans (they may have three or more “tails” on their reproductive cells). But evolution has offended roundworms because they have motile cells - there is not a single cilia or flagellum in their entire body. The reproductive cells of these animals have a plastic cell wall, which allows them to move with the help of pseudopods. Newts have a fin on the sperm. But there are variations not only in the tails, but also in the heads. If in humans they are ellipse-like, then mice and rats can boast of a hook-like shape.

The size of germ cells in men is extremely small - from tens to hundreds of micrometers. This variation has nothing to do with the size of the adult individual.

Discovery of sperm

Before scientists thought about the question “Where is sperm formed?”, they had no idea that there were special cells involved in the reproduction of humans and animals. And in general, they had a very vague idea about the structure of living tissues.

A revolution in science occurred in the mid-seventeenth century, when the Dutchman Antoine Leeuwenhoek invented a microscope and began to examine various objects through it: pollen, leaves and petals of plants, human and animal skin, and much more. In 1677, it came to germ cells. He described the egg and sperm, which he called the “sperm animal.”

Like any scientist, Leeuwenhoek first carried out all the experiments on himself, so human spermatozoa were described first, and only then other animals. The idea that these “animals” are involved in conception quickly occurred to Antoine, which he did not fail to report to the British Scientific Society.

Structure

If you do not take into account the length of the flagellum, the sperm is the smallest cell in the human body, about 55 micrometers. Such small sizes allow it to quickly move through the uterine cavity and reach the egg.

In order to be even smaller, in the process of sperm formation, they undergo a number of transformations:
- the core becomes denser due to the condensation of genetic material;
- the cytoplasm is separated into a separate “cytoplasmic drop”;
- only those organelles that are vital to the cell remain.

1. The head of the sperm has the shape of an ellipse, flattened laterally. Sometimes it can be concave on one side, and then we can talk about a spoon-shaped shape. The head contains:
   - a nucleus with a haploid set of chromosomes. This is necessary so that after the fusion of two germ cells, the total amount of genetic information is equal to that in somatic cells, otherwise the fetus will not survive or will have deformities. Due to the strong “compression” of chromatin, it is in an inactive state and cannot synthesize RNA.
   - the acrosome is an evolutionarily modified Golgi apparatus, it is necessary so that the head of the sperm can enter the egg.
   - centrosome - an organelle that supports the “skeleton of the cell” and ensures the movement of the tail.
2. The midsection or neck is the narrowing between the head and tail. It houses the mitochondrion, which produces energy for the movements of the flagellum.
3. The tail or flagellum is the thin, mobile part of the sperm. Performs rotational translational movements that allow the cell to reach its goal.

Function

The method and place of sperm production are closely related to its functions. And the main one is penetration into the egg and fertilization. To perform this function, nature has provided for the mobility, mass and chemical “attractiveness” of sperm.

Female and male organisms are designed to reproduce their own kind, so they are compatible physically, chemically and genetically. If a man takes care of his health, does not have bad habits, and has received all vaccinations on time (especially against mumps), then his reproductive cells will be ready to perform their function at any time.

Movement

The formation of sperm in men is associated, among other things, with the formation of a flagellum, which helps the cell move. During movement, the reproductive cell rotates around its axis at a speed of 0.1 millimeters per second. This is more than thirty centimeters per hour. They need to cover a distance of more than 20 cm. About a couple of hours after intercourse, sperm reach the fallopian tubes, and (if there is an egg there) fertilization occurs.

Inside the male body, sperm practically do not move, they are not active and passively move along the seminal ducts along with the seminal fluid due to peristaltic contractions of the ducts and the movement of the cilia.

Lifespan of sperm

Scientists, together with physiologists, tried to figure out the question of where sperm are formed and why they are periodically renewed? It turned out that the entire process of maturation of germ cells takes more than two months, but a large number of them are obtained. Due to this, men do not lack genetic material.

The viability of sperm lasts only for a month, and they need the right conditions:
- temperature not higher than 32 degrees Celsius;
- absence of inflammatory diseases.

And outside the male body, the cells retain their mobility for up to a day. Inside the uterus, this time can be extended to three days.

What is spermatogenesis?

Spermatogenesis is the formation of sperm, which occurs under the constant regulation of the body's endocrine system.

It all starts with precursor cells, which after several divisions take on the appearance of an adult sperm. Depending on the type of animal, the process of sperm maturation may differ. For example, in chordates, during the embryonic period, special cells are formed that migrate into the primordia of the gonads and form a pool of cells, which will subsequently become sperm.

Spermatogenesis in humans

The method of sperm formation in humans is no different from that of other vertebrates. The process begins at puberty (at age 12) and continues until almost 80 years of age.

According to some sources, the sperm maturation cycle lasts 64 days, according to others - up to 75 days. But the change of tubular epithelium (which is the substrate for germ cells) occurs at least once every 16 days.

The whole process takes place in the convoluted seminiferous tubules of the testicle. On the basement membrane of the tubules there are spermatogonia, as well as first- and second-order spermatocytes, which then differentiate into a mature cell. First, progenitor cells undergo several cycles of division by mitosis, and when there are enough of them, they switch to meiosis. As a result of this last division, two daughter spermatocytes are formed, and then two more spermatids. Each of these cells has half the set of chromosomes and can fertilize an egg.

The reproduction and maturation of sperm (spermatogenesis) is a continuous process that begins during puberty and ends in old age, unless it is disrupted by any disease or other harmful influence. Spermatogenesis occurs in the male gonads – testicles (testicles).

Anatomy of the testicles - sperm factories

The testicles are located in the scrotum, which is located outside the cavities of the human body. The skin of the scrotum is richly supplied with sweat glands to prevent overheating. The testicles have at their disposal a muscular apparatus that allows them to lift the testicles into the abdominal cavity (for example, when the ambient temperature drops, especially during sudden cooling). A spermogram is a sperm analysis that takes into account certain sperm parameters. Sperm is the secretion of the sex glands (prostate, seminal vesicles) in which sperm are located. The process of sperm formation is called spermatogenesis. Let's take a closer look at the entire mechanism of sperm formation and maturation.

Spermatogenesis is a continuous process that begins during puberty and ends in old age, unless it is disrupted by any disease or other harmful influence. Spermatogenesis occurs in the male gonads – testicles (testicles).
waiting). Both of these phenomena are well known to the male part of the population. These protective mechanisms are carried out reflexively with the participation of the autonomic nervous system, that is, they do not depend on the conscious will of a person. The testicles are oval in shape, slightly flattened on the sides, and with normal development in mature men they become the size of a plum. The left testicle is always slightly larger than the right one and is located in the scrotum below the right one. This phenomenon is associated with the anatomical features of the blood vessels that supply blood to the left and right testicle. Thus, the fears of some adolescents and some adult men regarding the asymmetry of the size and location of the testicles are in vain.

Physiology of the testicles

The testicles produce the male sex hormone testosterone. Testosterone is produced by Leydig cells, which are also called interstitial cells. In parallel with the process of testosterone production, sperm maturation occurs in the seminiferous tubules of the testicle. The seminiferous tubules are very extended - their length reaches 150-300 m. Such a phenomenal length of the seminiferous tubules is achieved by their incredible tortuosity. Through the outlet canals, of which there are 12-13 in each testicle, sperm enter the extremely convoluted, up to 5 meters long, duct of the epididymis (epididymus), where the process of their maturation ends. The sperm then enter the vas deferens or disintegrate.

Sperm development

How does sperm develop? At the beginning of development, the male reproductive cell, the precursor (spermatogonia), goes through several stages of mitotic division, during which the cell divides into two while maintaining the full chromosome set. As a result, a spermatocyte is formed, which represents the next stage of sperm development. The spermatocyte enters into meiotic divisions (in two stages), during which the chromosome set is divided in half, and, as a result, spermatids are formed. Spermatids no longer divide, but only undergo the process of maturation. As a result, the formation of a mature male reproductive cell - sperm.

What conditions are necessary for the normal development of sperm?

Under what conditions does the process of development and maturation of male germ cells take place? The optimal temperature for spermatogenesis is 34 ºС, and this process lasts 72-74 days. A healthy man produces about 100 million sperm per day. This process occurs continuously - some sperm complete their maturation, others are just beginning to grow, and others are in the middle stage. During this period, the impact on a man’s body of various unfavorable factors can have a negative impact on the development, mobility, structure, and, consequently, the biological ability of sperm.

What is unfavorable for sperm development?

What factors lead to impaired spermatogenesis? As we have already said, this is excess heat (both external and internal), prolonged fever, excessively frequent visits to the sauna or steam bath with a high temperature, and taking hot baths. Also, various toxic chemicals, ionizing radiation, electromagnetic waves, stress, hypocalcemia, congestion in the pelvis, poor circulation in the scrotum (long-term sitting in a sitting position - among athletes-cyclists, professional drivers, office workers) have a negative effect on spermatogenesis. wearing too tight underwear (pants), hypothermia of the pelvic organs (sitting on cold objects), infectious diseases of the genital area (prostatitis), endocrine diseases (diabetes mellitus, dysfunction of the thyroid gland).

Taking antibacterial and sulfa drugs, seemingly harmless, such as sulfasalazine, furadonin, long-term use of tranquilizers, antidepressants, alcohol, tobacco smoking, cocaine addiction, cannabism (smoking Indian hemp products - marijuana, hashish), mental influences (severe fear, for example) - all these factors also disrupt the normal course of sperm maturation.

Read more about prostatitis in the article: Prostatitis

How does fertilization occur?

Spermatozoa carry half a set of chromosomes (haploid) - 23 pieces, of which 22 chromosomes are somatic and 1 chromosome is sex. It is this sex chromosome that will determine the sex of the unborn child: if the sex chromosome is X, the child will be female, but if Y, the child will be male. Subsequently, during the process of fertilization, the haploid set of chromosomes of the sperm will combine with half the set of chromosomes of the egg (female reproductive cell). The genetic material of both parents merges and the number of chromosomal apparatus is restored to 46 chromosomes (23 maternal and 23 paternal).

Then the division and development of the future organism begins from this single cell, formed as a result of the union of the egg and sperm. The process of fertilization is depicted very schematically, but it is important that the two halves of the chromosome set are united like halves of loving hearts. In reality, these processes are quite complex and are subject to very fine regulation. The regulation of fertilization processes is built with a multiple system of protection and safety nets, however, they can also be vulnerable.

What does sperm consist of?

A mature sperm consists of a head, body and tail. The vas deferens, each for its part, passes into the abdominal cavity as part of the spermatic cord, through the inguinal canal almost to the bladder, where the seminal vesicles are located, secreting a protein secretion that promotes greater sperm motility, enveloping them in a kind of protective membrane. Next, the vas deferens pass through the prostate gland (prostate), which has the shape of a chestnut.

The prostate produces a secretion that enhances sperm motility. The property of sperm motility is ensured by a large number of enzymes and biologically active substances. The vas deferens flow into the urethra, and the ducts of the Cooper glands flow into it, releasing their secretion before ejaculation. At the peak of sexual arousal, involuntary contraction of the muscles of the walls of the vas deferens occurs, their lumen expands, and the seed comes from the ducts of the testicle. Subsequent muscle contractions expel seminal fluid, causing the man to experience a sensation of orgasm.

For more information about sperm analysis, read the article:

During every minute, a man's body produces 50,000 sperm. During every hour, his testicles produce 3,000,000 sperm. During each day - 72,000,000 sperm. This amazing process, coupled with incredible performance, begins at puberty and continues until death. Compare it with the maturation of eggs within 28 days, that is, once a month, in a woman’s body (and even then before menopause).

However, due to the size of the sperm, the amount of sperm released is not at all that large. If you were to collect together all the sperm that contributed to the conception of every human being who has ever lived or is alive, there would only be enough of them to fill a thimble. The sperm produced by a man during the day, collected together, would be no different from a grain of sand. Naturally, they are not visible to the naked eye, and their structure can only be studied using an electron microscope.

Male sperm is a complex substance consisting of more than 30 different components, including citric acid, fructose, highly concentrated potassium and such an important element as zinc. The composition of sperm also includes sulfur, copper, magnesium, calcium, vitamin C and B12, i.e., all the most important chemical elements for human health. In addition, the seminal vesicles contain 15 different prostate secretions that stimulate muscle contractions and dilation of blood vessels. Despite the presence of citric acid, semen has a slight alkaline property.

There are two types of sperm: some contain the sex chromosome X, others Y. Fusion with an egg of a Y-sperm leads to the birth of a boy, but an X-sperm? girls.

A study by Israeli scientists confirmed that the sex of an unborn child can most likely be determined at conception. It is believed that Y-sperm are more mobile, but have a shorter life expectancy. Therefore, if conception occurs during the period of ovulation, i.e., when a mature egg leaves the ovary, they manage to achieve their goal faster than X-sperm. Then a boy will be conceived. Conversely, if conception occurs a day before ovulation, then there is a greater chance of fertilization of the egg with an X-sperm, which has a longer life expectancy. And a girl will be conceived.

Newborn sperm

"Newborn sperm" are microscopic germ cells. They are grouped in the testicles in ranks, like soldiers on parade. As they develop, they form an oval-shaped head, a thin neck and a tail (flagellum), long compared to their microscopic size. The sperm contains a set of 23 chromosomes, which are located in the head and contain genes that transmit family resemblance traits to future generations. Spermatozoa move using a flagellum. The blows, reminiscent of a whip, propel them forward on the long journey to the awaiting egg.

Of the multi-million army of sperm released during one ejaculation (ejaculation), only one can penetrate the egg. A fertilized egg develops a special kind of protection that prevents other sperm from penetrating into it. For the normal process of fertilization, it is important not only the formation of a sufficient number of full-fledged sperm, but also a certain composition of the liquid part of the sperm: the optimal concentration of fructose, zinc and calcium ions, biologically active peptides and a low level of acidity. The state of these indicators is influenced by the level of hormones and radiation, the action of certain chemicals and even the psycho-emotional state.

The sperm's tail moves like a snake, bending in several places at once. The lower part of the tail must wag from side to side 800 times for the sperm to move forward 1 cm.

Testicular activity

The testicles can be compared to a conveyor belt, as they work without interruption. The activity of each sperm-producing seminiferous tubule does not stop for a minute. The huge conveyor line moves tirelessly forward without smoke breaks, lunch breaks or overnight downtime. When the finished product comes off the line, some of the cells left behind are halfway through, while others are just beginning to live. At each stage of development, a specific rhythm and speed of movement is observed, which can neither be slowed down nor accelerated. The formation of a germ cell takes a long time, about 72 days. At the end of the production process, not all of them are in perfect shape. Some have no flagellum, others have an underdeveloped head, and others are deformed. This was to be expected with such mass production. Several million poorly formed, unformed sperm do not reduce a man's ability to fertilize. Inside the testicles, male cells can only make small movements.

Activities of the epididymis

The epididymis are long, narrow tubules that lie curled up above both “twins.” When sperm production ends, they move from the testicles to the epididymis. They are not yet sufficiently developed, unable to move properly and fertilize an egg. Sperm motility is an important factor in fertilization ability. To win the race, the male cage must move forward and only forward, without changing direction. Spermatozoa acquire motility only in the initial part of the epididymis. The walls of the epididymal duct secrete fluid, under the influence of which the sperm begin to move. But they still have a poor sense of direction, which forces them to swim in a circle, that is, to remain in place. This means that they would lose the race to the egg in disgrace. The maturation of sperm in the tubules of the epididymis lasts twelve days before they sufficiently learn to swim. At this time, the most sensitive muscles located in the walls of the tubules push them forward. The enormous distance they have to overcome is about 6 m. The liquid nutrient medium serves as food for them, helps them mature and gain the necessary mobility. To sum it up, we can say that the epididymis is a real school of courage.

Short shelf life of sperm

Sperm need to spend 72 days in the testes and 12 days in the epididymis to reach maturity, a total of almost 3 months. Only after this are they ready to set off on the long journey to the seminal vesicles and further to the prostate gland. Mature germ cells accumulate in the epididymis, but not for long. They have a limited shelf life. They remain “fresh” and active for less than a month. After this, they age sharply and soon die. Dead sperm decompose, and the nutrients they contain, including proteins, are absorbed by the testicles. If a man ejaculates only once a month, it seems to him that he is no longer able to impregnate a woman. He thinks his sperm are too old, or dying, or have already died. But in fact, the production of male reproductive cells is a continuous process. Millions of new sperm enter and travel through the epididymis in an endless stream. Although the ejaculated sperm may contain old sperm, along with them there are also completely new ones, ready to begin the race to the egg and realize their chances.

The male reproductive cell develops about 75 days from the moment of its occurrence. Therefore, the consequences of harmful effects may take several months to appear. Some relative guarantee of the correct development of germ cells is provided by strict adherence to nutritional standards. Scientific research suggests that excess weight in men leads to changes in testosterone and estrogen levels? the main hormones responsible for the formation of sperm. In addition, with excess weight, the temperature of the testicles increases, which for successful sperm formation must be lower than body temperature. For the same reason, frequent hot baths are undesirable.

Sweet seed

Sperm (seminal fluid), produced by the male gonads, consists of sperm, seminal vesicle fluid and prostate secretion. Sperm make up on average only 3% of the ejaculate. The remaining 97% is the secretion of the prostate gland and the fluid of the seminal vesicles. In the first portion of ejaculate, the sperm content is higher than in subsequent ones, and especially in the last. The ejaculate contains approximately 300 to 500 million sperm. Sperm is a complex liquid, saturated with various compounds and sugar, and not all components are known. Fructose (a sugar found in semen) may serve as an energy source for sperm, but this remains to be proven. Semen is alkaline, while vaginal secretions are acidic. It is generally accepted that the alkaline substance coats the sperm and protects them while they are inside the vagina. Prostate secretion contains strong antibacterial compounds. The sperm is released in a liquid state, then it quickly turns into a jelly-like state, and after 20 minutes the sperm liquefies again. It is possible that this helps germ cells survive in the vagina. The average volume of ejaculate, provided that orgasm occurs with 3-day intervals, is from 3 to 5 cm; the quantitative expression of the ejaculate may vary depending on age, health status, amount of fluid drunk, and so on. In a partner, sperm can cause an allergic reaction. The allergy manifests itself in the form of a rash or prolonged itching of the reproductive organs. This happens extremely rarely; most often, such symptoms indicate the presence of an infection.

In addition to its direct function of fertilizing the egg, sperm has a positive effect on the woman’s body, except, of course, in those cases when it becomes a carrier of diseases (AIDS, hepatitis, sexually transmitted diseases). Based on this, hormonal contraceptives, on the one hand, are preferable to condoms, on the other? the latter remain the most effective means of preventing infectious diseases transmitted through sexual intercourse.

In a partner, sperm can cause an allergic reaction. The allergy manifests itself in the form of a rash or prolonged itching of the reproductive organs. This happens extremely rarely; most often, such symptoms indicate the presence of an infection.

It is no secret that some French manufacturers use sperm to make cosmetics. This cosmetics is very effective and is not cheap. The thing is that in nature there is no more valuable and unique product than sperm. The cosmetic value of sperm is determined by the presence of extremely useful substances in its composition.

It turns out that the world-famous Viagra and some other popular drugs for impotence do not increase sperm activity, as one might expect, but inhibit it, which negatively affects the ability to fertilize.

Small leak

Before ejaculation, a small drop of liquid wets the end of the penis. It comes from the Cooper's gland and produces a strong alkaline reaction that neutralizes all traces of acid after urination. It cleans and rinses the urethra, preparing it for the passage of sperm. This fluid contains several thousand sperm. There is a theory that this is a "team of superstars" ready to win the race. To avoid conception, even a small part of this fluid should not enter the vagina, otherwise sperm may find their way to the egg. Removing the penis from the vagina just before ejection of semen is called coitus interruptus. This method is often used by young couples trying to avoid pregnancy. However, they are at great risk of becoming mom and dad in nine months. The culprit is often a small drop from the Cooper's gland. Coitus interruptus requires skills and the ability to control one's reactions and manage orgasm, which are most often absent in youth. This can cause a lot of stress for partners. However, many experienced, mature couples choose this particular method of protection, the most ancient and widespread. But it does not protect against infection with sexually transmitted diseases and AIDS, while a condom provides at least partial protection.

Survival of the fittest

It is generally accepted that only 200 sperm survive the journey to the egg. Some are unable to overcome the very first obstacle - the cervix, while others die while moving through the uterus. Still others may get confused and not get into the right oviduct. A sperm can live in a woman’s birth canal for 2 to 7 days. This is how long it may take for an egg to be fertilized. When it comes to sperm, it is true that quality is more important than quantity. The key issue is the problem of mobility: the cell must swim in only one direction, that is, forward. The average sperm speed is 3 mm per minute. The faster ones have a better chance of reaching the goal before they die. So, speed and mobility are the main conditions for winning races. Those lucky enough to survive accumulate in the widest part of the oviduct. This is where they eagerly await the arrival of the egg. If she is already in place, they gather around her, selflessly trying to break through her protective shell. Wriggling, the sperm sharply hits the outer wall of the cell, releasing chemical compounds that dissolve its protective layer. Eventually small holes appear in the wall and a few lucky sperm make their way inside the egg. From those who succeed, only microscopic heads remain. Now they face the last obstacle, the last bastion that needs to be taken. This thin outer shell protecting the nucleus of the egg is the most difficult obstacle. And only one sperm can overcome it. Perhaps they really will be the best of the best. Its head moves to the middle, and its nucleus connects with the nucleus of the egg. Conception occurs - total implosion, perfect fusion, complete union of two nuclei. According to generally accepted ideas, this reunion is a manifestation of a powerful, all-encompassing micro-force. It is this that determines all the parameters of our personality. Chromosomes join in pairs, once and for all determining a set of hereditary traits. The new life is a perfectly proportional, democratic mixture of the genes of both parents.

Infertility problem

Infertility is the body's inability to produce offspring. According to one study, 15% of American and 12% of English couples face infertility problems, and in 35% of cases this is due to male infertility. In 10-15% of cases, the reason lies in the infertility of both partners. Experts say that there is cause for concern only if conception does not occur within a year of intense sexual activity. Some of them believe that this period should be extended to a full 18 months. Currently, male infertility is becoming more common, and the cause of this phenomenon is unknown. In 1950, the average number of sperm per semen was 40 million higher than in 1988. One of the most important reasons may be overheating of the testicles (staying in hot water is a primitive method of contraception). Tight clothing can act in a similar way, increasing the temperature in the groin and perineum area. Studies to establish the relationship between the type of underwear and fertility have shown that men who wore boxer shorts had a higher sperm count than those who wore tight underwear. Unfavorable environmental factors (radiation, air pollution with lead compounds and other toxic substances, etc.) also have a harmful effect on the quality of sperm. Currently, the prevailing opinion is that they cause much more damage to health than was commonly believed. The testicles are more exposed to harmful environmental influences than the internal organs. Therefore, you should remember that the testicles are an extremely sensitive organ, and avoid anything that involves unnecessary risk.

Insufficient intake of vitamin C (less than 60 mg per day) has a negative effect on sperm health and is believed to affect the occurrence of various disorders in the offspring. Well-known risk factors are tobacco, alcohol and drugs. Anabolic drugs that bodybuilders are addicted to are also very dangerous. Not all men remember the health of their offspring when choosing a profession. And statistics show: among painters, floor polishers and other people who work with paints and varnishes, the quantity and quality of sperm changes, and anomalies are more common in their children. And, for example, the wives of dentists have an increased risk of miscarriage due to the fact that their husbands inhale fumes of narcotic substances that are administered to patients. Studies of the sperm and offspring of computer scientists have so far yielded conflicting results. And yet, experts advise both men and women engaged in such work to interrupt or limit it at least a month before possible conception.

Sperm are most mobile in autumn and winter; at the same time, sperm contains the maximum concentration of germ cells. Scientists recommend the months from October to February as the most suitable for conception. In addition, during these months the likelihood of conceiving a boy is greatest because in the summer, due to the heat, the Y chromosomes, carriers of the male genetic code, are much inferior in viability to the female X chromosomes.

A change in the maturation process of sperm, a decrease in their number, motility, and the presence of chromosomal abnormalities in them can cause male infertility, which, although somewhat less common than female infertility, requires no less thorough research and treatment.

Sperm volume

The amount of sperm sufficient for conception is from 2 to 5 cm. If the ejection volume is less, the sperm becomes thick and viscous, and the sperm are poorly protected from the effects of acidic vaginal secretions. If the volume is larger, then the sperm is too diluted, and there is a high probability of germ cells scattering into the vagina. Don't lose hope! If the results of the analysis are not in your favor, do not despair. In vitro, sperm die much faster than in the body. In vitro they live only from 2 to 6 hours. The stress associated with taking the test and the fear of being diagnosed with infertility can negatively affect the results. People tend to make mistakes, and this can easily happen within the walls of a laboratory. The results may be affected by poor quality packaging, errors in calculations, or improper storage. Perform several (2 to 3) tests over 6-7 weeks, changing laboratory technicians. Only after this, if all the results are clearly negative, decide what to do next. Rare congenital anomalies include dysfunction of the testicular tubules that produce sperm. The germ cells begin to turn into sperm, but most of them do not mature. Currently, highly qualified specialists can separate mature sperm and use them to fertilize an egg outside the woman’s body. Male infertility remains a poorly understood problem. Therefore, try to avoid treatment in clinics that have not received official recognition. Instead of surgery to remove the nodes of the vas deferens or testicular biopsy, you can resort to artificial insemination of the partner with your own or donor sperm. However, these operations are expensive both materially and psychologically and do not always give a positive result. Regardless of your decision, try to feel like a man. Drive away gloomy thoughts, they only increase the state of tension and weaken self-confidence. Don't lose hope and keep trying. You should know that there have been cases where men with hopelessly low sperm counts surprised specialists, their partners, and themselves with unexpected paternity.

Myths about sperm

“You may run out of sperm” This naive and ridiculous idea of ​​the processes occurring in the body is widespread among boys who frequently masturbate. But a surprisingly large number of mature men believe this. Moreover, although the vast majority of men know that the body produces sperm throughout life, this opinion cannot be dispelled. Abstinence does not affect sperm quality in any way. Recently, studies were carried out on sperm 12 and then 120 hours after the last sexual intercourse. Analyzes showed that abstinence had no effect on the shape, motility, or number of sperm. However, long-term abstinence causes a decrease in the number of high-quality sperm.

"Ejaculation depletes the body"

This misconception is closely related to the previous one. For a long time, coaches and sports team leaders demanded that their players abstain from sex at best 4-5 days before the start of important sports competitions. Recently, scientists at Colorado State University studied the physical fitness of athletes who: a) abstained from sex for 5 days, b) had sex within the last 24 hours. They were tested: endurance, readiness for effort, mobility, reaction speed, balance, muscle strength and other indicators important for athletes. The researchers noted "no significant or measurable differences" in both groups of athletes.

"In old age, sperm are no longer produced"

At age 70, sperm production declines. But studies show the presence of sperm in the ejaculate of 48% of men aged 80 to 90 years. Currently, most scientists agree that older men have less viable sperm than younger men. There is a slight increase in the number of deformed sperm, which can cause developmental defects in the conceived child. The degree of risk in such cases cannot be determined, since a man at this age no longer strives to become a father.

One of the most pressing questions that worries any person is the question: “Why do we live?” It cannot be answered unambiguously, but there is one undeniable answer: the meaning of life for any living creature, including humans, is to leave behind offspring, to create conditions for children to grow up healthy and also be able to “inherit” your immortal genes.

Unlike animals, for humans, having children is not the only purpose of existence. An important place in our lives is occupied by education, professional self-realization, interesting communication, new experiences, for which some people turn to TV, while others go on trips. Human sexuality today includes not so much a procreative function (reproduction), but recreational (receiving pleasure) and relational (communication with a loved one, cognition and self-awareness, unity) relationships. The birth of a child in most cases is no longer an unconditional reflex act, but a reasonably planned event in the life of a family. But the biological basis of reproduction remains in principle the same as millions of years ago, when the first mammals appeared. And, in fact, the sexual aspect has changed little, i.e. behavior aimed at preserving the family: choosing and “conquering” the most promising partner in reproductive terms, caring for the future mother and children, teaching the offspring the necessary life skills. Does anything in this chain of actions depend on us or did nature wisely provide for everything itself?

Is it possible to “plan” the sex of a child?

Most people know that the sex of the unborn child depends on the man. Unlike women, who have two sex X chromosomes of the same size and shape in their cells, men have one Y chromosome and one X chromosome in their cells. The Y chromosome contains hereditary information that directs the development of indifferent gonads along the male path, turning them into testes.

When chromosomes diverge during cell division, which occurs in the testicles during the formation of germ cells, each sperm gets 23 chromosomes from the original 46, i.e. Not only does the number of chromosomes in each cell decrease by half, but also the exchange of similar sections of chromosomes that the man once inherited from his father and mother occurs. That is why all sperm turn out to be genetically different and carry different sets of characteristics. In this case, from a pair of sex chromosomes, one sperm gets a Y chromosome, the second - an X, so half of all sperm contain a Y chromosome, half - an X. If an egg is fertilized by a sperm of the first type, a boy will be born, and a girl of the second type will be born. These processes are random and do not depend in any way on the will and desire of the future father or on his lifestyle. Therefore, during natural conception floor planning a future child is impossible. No amount of diets or predictions from astrologers will help here; the birth of a child of the desired sex can be achieved only after fertilization of the egg “in vitro”, when a genetic study is carried out to find out which chromosomes are contained in the sperm being studied, and embryos of the desired sex are transferred into the uterine cavity.

When will pregnancy occur?

When planning the birth of a child, you need to remember that the onset of pregnancy is a process that depends on many factors: the quantity and quality of sperm in the pregnancy, the presence and timing of the female egg (the release of the egg from the ovary), the patency of the fallopian tubes, etc. It has been shown that the probability of conception depends, among other things, on the frequency of sexual intercourse: in healthy partners with sexual intercourse 2 times a week, the probability of pregnancy during one female cycle is 20-25%, with a frequency of 4-5 times a week it increases to 40-42%. The likelihood of conception with repeated sexual intercourse is reduced due to the fact that the second portion of sperm contains fewer full-fledged sperm, and the excess volume leads to its leakage from the vagina. Currently, it is generally accepted that pregnancy should normally occur within a year of regular sexual activity without contraception.

Of course, the likelihood of pregnancy depends on the quality of the sperm. The lower the number of sperm, the more immobile sperm, the less chance that the egg will be fertilized. It is important to remember that a man's potency does not automatically confirm his fertility, i.e. ability to have children. There are often cases when sexually weak men have excellent sperm and, conversely, sexually active men have reduced sperm content or no sperm at all. The quality and potential fertilizing ability of sperm can be assessed only after special laboratory tests, which include determination of the number, motility and structure of sperm, the acrosomal reaction 1, which characterizes their functional maturity, and the presence of antisperm antibodies 2.

1 During the interaction between the sperm and the egg, an acrosomal reaction of the sperm occurs, during which enzymes are released from a part of the sperm - acrosomes, which destroy a small area of ​​the egg shell.
2 Antisperm antibodies are antibodies to male sperm that are found in the blood of men.

It is now generally accepted that men (and males in general), although they are considered the “strong” sex, are more susceptible to negative environmental factors. Evolutionarily, this is due to the peculiarity of their biological role. Males in nature are the main material of evolutionary selection, various combinations of genes that nature tries for survival. (It is well known that more boys are born, but fewer survive than girls.) The appearance of offspring is also a “reward for courage,” which in the animal kingdom does not go to all males. Every day, a man produces tens and hundreds of millions of sperm, and they are all genetically different, while a woman only produces 1-2 eggs every month. Of these millions of sperm, only one fertilizes the egg - it has passed through the sieve of natural selection, which first occurs in the genital organs of the man himself, and then continues in the genital tract of the woman. The basis of selection is that all sperm are genetically different. Sperm selection begins in the testicles themselves, then continues in the epididymis and seminal vesicles, where sperm accumulates before ejaculation. It is estimated that a normal man produces about 100 million sperm every hour, and the semen after abstinence for several days contains several tens of millions of them, i.e. 100 times less. “Defective” sperm are eliminated (removed) by special eater cells. Of those sperm that enter the vagina, less than 1% of the cells also pass through the cervical canal into the uterus: only a few hundred participate in the siege of the “fortress” that is the egg.

The maturation process of sperm is much faster than that of eggs. In men, the duration of spermatogenesis is about three months. In women, reproduction of germ cells occurs in the prenatal period. Each of them, no more than 30 potential eggs enter further maturation, of which one dominates at the last stage.

We can say that a man, in evolutionary terms, is the bearer of genetic and behavioral mobility. A woman, on the contrary, is a genetic “conservator”: she preserves and passes on to children what was accumulated by previous generations. Therefore, the causes of female infertility are much more often associated with malfunctions in the functioning of the female body itself, while external circumstances often have a fatal influence on a man. If conditions are unfavorable, offspring should not appear. This regulation is ensured by the close relationship between the reproductive system and all other systems of the body, primarily the nervous system. Reflation of sperm formation is carried out by the hypothalamus and pituitary gland - structures located in the brain, with the participation of other organs of the reproductive system: appendages, prostate, vesicles, etc. At each stage of this process, disturbances can occur.

Male infertility: risk factors

What can cause a decrease in a man’s reproductive potential?

Some factors are congenital, caused by genetic abnormalities or developmental defects. This includes genetic syndromes of Klinefelter, Raifinstein, Kalman, etc., as well as the absence of certain elements of the genitourinary system. In this case, there are very few or no sperm in the semen, which makes pregnancy in a natural cycle almost impossible.

Many of the risk factors are "man-made" and depend on lifestyle person. Among them, the most widespread are smoking, alcohol abuse, unhealthy diet, sedentary lifestyle, psycho-emotional stress, lack of sleep, as well as sexually transmitted infections.

Inflammatory processes in the genital organs or even asymptomatic carriage of infections such as chlamydia and mycoplasma are one of the most common causes of infertility. The infectious process leads to damage to spermatozoa by active radicals and other factors of inflammatory reactions, obstruction of the reproductive tract - the formation of spermatozoa in the path, disruption of the endocrine function of the gonads, and the development of immune reactions against one’s own spermatozoa. If antibiotic treatment is started promptly, sperm quality problems are usually reversible. If the process has become chronic and led to organic changes in the organs of the reproductive tract, the prognosis is less favorable.

Low physical activity, sedentary work, passive rest, too tight jeans and tight underwear, excess weight, deposition of lipids (fatty acids and their derivatives) in the vessels disrupt blood circulation in the pelvic area and lead to stagnation of blood in the vessels. Where there is stagnation, there is a deficiency of oxygen, an increased content of metabolic products, and inflammation. The causes of varicocele, a male disease in which the veins of the spermatic cord are dilated, are associated with overheating and the accumulation of harmful metabolic products. This is usually observed in the left half of the scrotum. Circulatory disorders are aggravated by overheating and vibration, so professional drivers who spend more than four hours a day behind the wheel have a higher incidence of infertility than men in other professions. The problem of the influence of elevated temperature on fertility is purely male. It is no coincidence that the place of sperm formation - the testicles - is located in a special skin bag - the scrotum. The temperature in the scrotum is normally several degrees lower than body temperature. Therefore, too warm trousers, especially synthetic ones, thick blankets or electrically heated blankets, constant baths, saunas and hot baths negatively affect the quality of sperm. Finnish researchers found that those who visit the sauna twice a week have a statistically higher risk of developing it compared to those who steam once a week. Any febrile conditions such as influenza, measles and other diseases lead to a deterioration in sperm quality, and such a decrease in quality can be observed for up to 3 months. — this is how long each sperm continues to mature in the testicle and epididymis. Fortunately, damage caused by moderate overheating is usually reversible.

All men know that the groin area is very sensitive to any blows. Bruises, ruptures, and cuts of the testicles in the vast majority of cases lead to infertility. But recently, including our research, it has been convincingly proven that even mild injuries that do not immediately cause serious consequences, which the patient has difficulty remembering, trigger an invisible mechanism of autoimmune warfare, when the immune system “attacks” its own cells. Many years after such a trauma, it turns out that the body has long ago turned against the sperm it produces itself and the man has immune infertility. Risk groups here include martial arts athletes, wrestlers, and cyclists.

Separately, it is worth mentioning alcohol consumption. In small quantities, alcohol is not dangerous, it even improves blood circulation, and today it is considered as a preventive measure for diseases of the vascular system, and these diseases often affect the quality of sperm. But a safe dose of alcohol is about 25 milliliters of alcohol per day, that is, 150-250 grams of dry wine or 60 grams of vodka. Exceeding this dose turns alcohol from a “medicine” into a poison. How many Russian men are able to limit themselves to a glass or two of wine? In situations when it comes to planning a pregnancy, it is better not to drink at all than to drink too much.

It is well known that smoking not only has a direct toxic effect on the body, but also leads to prolonged vascular spasms, causing the same vascular disorders that are detrimental to sperm. It is especially bad when smoking is combined with other risk factors: excessive alcohol consumption, sedentary lifestyle, overheating, stress. And when risk factors are combined, their negative impact is multiplied and intensified tenfold. A healthy lifestyle is incompatible with smoking.

Chronic stress is a common and quite dangerous risk factor for the development of infertility in men. The function of sperm production is not necessary to maintain the life of an individual. This product of the gonads is addressed to the future. But it is obvious that from a biological point of view, offspring should be born in the most favorable environmental conditions, which will allow still helpless creatures to survive. Therefore, any stress - a reaction to threatening situations - is a signal to the body about unfavorable conditions and the need to stop childbearing. As a result of the interaction of the nervous, endocrine and reproductive systems, this leads to suppression of the process of sperm formation and the development of temporary sterility.

Do you need to prepare for conception?

So, if you are planning to expand your family, then both spouses should prepare for this joyful event. The minimum preparation period for a man is 3 months, which is how long it takes for sperm to mature. During this time, in addition to natural restrictions on smoking and alcohol, the future father should refuse to visit baths and saunas, as well as work with various varnishes, paints and hydrocarbon-based solvents. Heavy metals, contact with sources of ionizing radiation and powerful electromagnetic microwave radiation also pose a potential danger.