How long does it take for the sperm to reach the uterus? How long do spermatozoa live after ejaculation

The time that sperm cells live after intercourse in the conditions of the female body depends on the quality of the seminal fluid. This greatly affects the reproductive health of men. If, after sexual intercourse, spermatozoa do not end up in the vagina, then their activity time is much lower and depends on external factors. Ambient temperature has a direct influence. The survival of sperm at low temperatures is used in reproduction.

fertilization process

Spermatozoa have a rectilinear movement, the absence of morphological pathologies and the ability to further advance in the uterus. Some of them, after ejaculation, immediately pour out of the vagina, and about 15% enter the cervical canal.

At the next stage, they must overcome the path to the egg, directed against the flow of fluid in the fallopian tubes and vagina. During this period, about 80% of the remaining gametes die. Before the egg, they need to overcome a distance of more than 17 cm, the speed of their advancement does not exceed 4 mm per minute. Therefore, the process can be delayed for 2-3 days. But not all spermatozoa live that long, so their viability directly determines a man's fertility.

In order to correctly assess the survival of male germ cells, a spermogram and a postcoital test are performed. In the second case, a few hours after intercourse, a sample of the cervical canal fluid is taken from a woman and it is determined whether there are viable and. Their absence means poor sperm survival or an aggressive environment in the woman's cervix. The latter reason can also often lead to a lack of conception.

Life span of spermatozoa

Favorable conditions are necessary for sperm to survive. Their life expectancy depending on the environment:

Causes of sperm death

Male sex cells become non-viable with the following pathological factors:

• Varicocele. It's varicose. It affects not only the viability of the sperm, but also the mobility. It is treated only by surgical methods.
• Radiation sickness. Irradiation leads to a slowdown in cell division, a decrease in the number and viability of spermatozoa.
• Intoxication. The constant use of drugs and alcohol, smoking can have an impact.
• malnutrition. Chemical additives and preservatives in food, obesity can lead to pathology. Diets that contain a small amount of fat can also have a similar effect. Because fat is a precursor to testosterone.
• Other reasons. Hormonal disorders, STDs, viral diseases (mumps).

Spermatozoa mature in the testicles for 74 days. At the time of ejaculation, about 30 million of them enter the vagina - a huge amount. But at each stage of advancement to the egg, there are fewer and fewer "tadpoles". Surely you are interested to know how long sperm cells live and under what conditions, because only a few reach the eggs, and only one fertilizes.

A large number, about 10 million, die in the acidic environment of the vagina, never reaching the cervix, or spill out. Only 15 - 19 million enter the uterus. Another 10-13 million will not be able to travel a long way in the uterus and fallopian tubes, as the fluid in them flows against the movement of the sperm. Only 3 million (at best) will get a chance to get close to the egg, which is found because it releases pheromones.

Spermatozoa in the vagina and uterus move at a speed of 0.1 mm per second, in other words, more than 30 centimeters per hour. Fertilization is possible (provided that the woman has ovulated) already 1-2 hours after intercourse, when the first spermatozoa reach the fallopian tube.

After ovulation, the egg is capable of fertilization for 12-24 hours. As can be seen from the speed of movement of spermatozoa given above, this time is quite enough for the tadpoles to have time to get to it. Before and after this time, pregnancy is impossible. Ovulation is the rupture of a mature follicle and the release of an egg from the ovary into the fallopian tube.

The structure of the sperm in the picture:

How long do spermatozoa live in different conditions

How long do spermatozoa live in different conditions after ejaculation:

• In the vagina, they live no longer than 2 hours. The natural environment for the vagina is acidic. This is due to disinfectant functions, in which tadpoles can die after 20 minutes. In alkaline (for example, douching with a weak solution of soda), spermatozoa will live for a maximum of 2 hours.
• In the air, on the penis, on a condom and in a condom, they die after 15 minutes.
• In a condom with spermicidal lubricant, they die instantly.
• In the ejaculate (seminal fluid), provided that they are stored in a sterile jar (relevant, for example, for taking a spermogram), spermatozoa live no more than 2 hours.
• Spermatozoa caught on bedding die almost instantly due to contact with air and lack of moisture.

The health of a man, the absence of inflammation in a woman, the temperature of the room where sexual intercourse takes place affects how long spermatozoa live. At temperatures above 37 degrees, they die.

How long do X and Y live - spermatozoa in a woman's body

How long do X and Y - spermatozoa live in a woman's body after intercourse:

• In the vagina, they die after a maximum of 2 hours.
• Spermatozoa that have reached the uterus, carrying the Y chromosome responsible for the formation of the boy, are smaller and heavier, more active (than those responsible for girls). They live a maximum of 24 hours, prefer alkaline pH.
• Spermatozoa with the X chromosome are more massive and slower. Able to live 3 days in a woman's body and wait for an egg in the fallopian tubes. In rare cases, live up to 7 days.

Successful fusion of sperm and egg is possible only at the time of ovulation in a woman. Ovulation is a physiological process of the female body, when a ripe and ready for fertilization egg leaves one of the ovaries into the cavity of the fallopian tube. In order to consider this process in more detail, let us trace the path of the spermatozoon to the egg and how it penetrates through the protective layers, as well as the development of the fertilization process itself.

How does the sperm enter the uterus and how long does it take to reach the egg?

Sex cells in a male person are produced constantly from the moment of puberty until old age. For women, the situation is much more complicated. The development of an egg capable of procreation occurs periodically - 1 time in 28 days (with a normal menstrual cycle). Thus, the ability to conceive a woman appears only once a month for 1-2 days. A man, however, does not lose this ability throughout the entire reproductive age, and the ability to conceive in each person depends only on the quality of the seminal fluid produced.

Fertilization occurs when the fusion of the egg and sperm is successful. For this, the following conditions must be met:

• Ovulation occurs in the female body.
• Spermatozoa have all the necessary physiological parameters.

After ejaculation in humans, tens of millions of spermatozoa enter the female body. Only one can get to the egg and penetrate it - the fastest and most viable. Spermatozoa are capable of fertilization much longer than female gametes. Therefore, if sexual intercourse occurred one or two days before the onset of ovulation, the possibility of fertilization is quite high. In this case, the spermatozoa in the uterus have time to get to the place of fertilization before the egg, and then the chances of their successful fusion increase.

With contractions of the uterus, the seminal fluid enters its cavity, however, on the way to the uterus, part of the spermatozoa dies due to the acidity of the vaginal environment or the mucous plug in the cervical region. Part of the spermatozoa do not reach the uterus and die due to the low ability to survive. The rest, the most active male sex cells, move towards the egg at a speed of about 2 mm per minute. Thus, it is quite easy to determine how much time will pass before the sperm enters the egg. On average, this period is estimated at 4-6 hours. The life span of the eggs, during which they can be fertilized, can reach up to 48 hours. Further, the cells are destroyed, and the formation of new ones occurs only in the next menstrual cycle - after 1 month.

fertilization process

Fertilization of an egg is a complex process. In the female genital tract, spermatozoa move randomly, without a definite trajectory. In an accidental collision with an egg, under the influence of certain enzymes, the gametes merge. These substances are produced by the membrane of female germ cells, and thanks to them, spermatozoa are activated. On the head of each male reproductive cell is an acrosomal capsule that produces active substances that can destroy the protective layer of the egg. After the shell is partially destroyed, the acrosomal filament penetrates deep into the egg, firmly connecting the two gametes to each other. The egg and sperm are attached to each other and are ready for fertilization.

The entire content of the sperm head is absorbed into the egg along with the nucleus and fertilizes it. The shell becomes more vulnerable, all the physiological processes that took place in the cell itself change. She begins to actively eat, accumulating useful substances for the further development of the embryo.

If we consider two processes of the formation of germ cells - spermatogenesis and oogenesis - then we can see that each human germ cell has a half set of chromosomes. When cells merge, the number of chromosomes doubles, a new cell is formed, in which, after a while, an embryo with a completely new set of DNA is formed. The sex of a person is determined by what type of sperm reached the egg. In total, there are two types with a certain set of chromosomes, including X or Y. If a male germ cell containing a Y chromosome participated in fertilization, then the sex of the embryo is male. No folk methods and signs are able to determine this with accuracy, just as it is impossible to plan the sex at conception.

As a rule, when the egg and sperm unite, the result of fertilization is the emergence of a new life - the development of a human embryo. Usually one embryo is formed, but there are cases when two or three embryos occur simultaneously. This can happen when the spermatozoa, penetrating the shell of the egg, fertilize two or more nuclei if the cell is multinucleated. One of the manifestations of this process is the development of twins, very similar to each other and protected by one amniotic membrane. In this case, the sex of the embryos in most cases coincides.

In some cases, in the female body, several gametes capable of fertilization mature at once. Spermatozoa, having merged with the egg, contribute to the formation of two or more fetuses. At the same time, their development occurs in different fetal membranes, the embryos are not similar to each other and may have a different gender.

Recently, artificial insemination has become increasingly popular. The presentation of this method was first held in 1977 in the UK. Ten years later, the technology was applied in the Soviet Union and is still being successfully carried out in Russia. IVF is an effective way to solve problems with infertility. The fusion process takes place outside the uterine cavity and includes the following steps:

1. Partner survey.
2. Obtaining eggs capable of fertilization.
3. Obtaining seminal fluid (spermatozoa).
4. The choice of material for fertilization.
5. Fertilization of the egg (fusion of gametes).
6. Embryo cultivation.
7. Embryo transfer to the uterus.

Indications for such a procedure are different: endometriosis, obstruction of the tubes, ovulation disorders, infertility for unknown reasons. Experts also recommend going to an IVF consultation if the couple does not conceive naturally for more than 1 year.

During artificial insemination, two or three eggs are usually placed in the uterine cavity. Not all embryos take root in the body. But it also happens that IVF results in twins and triplets. In any case, artificial insemination does not give a 100% guarantee of conception and successful delivery.

Embryo Attachment

After successful fertilization, the egg begins to move through the fallopian tubes and within a few days reaches the uterine cavity. The speed of its movement is influenced by many factors, including the length of the pipes themselves. Penetrating into the uterus, the embryo is attached to one of its walls. How long the attachment of the egg takes depends on the state of the surface of the walls and their readiness for fusion. Usually the duration of this process is no more than three days. It is possible to speak about embryonic development only on the eighth day from the moment of fertilization. The most important physiological processes for the fetus occur in the first 12 hours of life.

If the fertilized cell could not pass into the uterine cavity, then a serious developmental pathology arises - an ectopic pregnancy. In this case, the further development of the embryo is out of the question, since the woman needs urgent surgical intervention. Otherwise, a rupture of the fallopian tube may follow, which in case of untimely medical care leads to death.

The place of attachment is important for the further growth and development of the baby. If the attachment happened too low and the developing placenta overlaps the uterine os, this pathology is called low placental. This is not a definitive diagnosis. During the period of fetal formation, the placenta migrates into the uterine cavity and rises in 90% of pregnant women by the middle or end of the pregnancy.

07.12.2011

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Each ovulatory menstrual cycle sets up a woman's body to conceive a child. Each egg is ready to be fertilized, but the spermatozoa located in the tubules of the testicles are practically immobile and incapable of fertilization. They acquire mobility while in the tubules of the epididymis for several days.

The path of the sperm to the egg

Let's skip the details of how the sperm enters the vagina and go straight to the moment when they have already got there. The main difficulties are still ahead - it is difficult for a spermatozoon to get to the fallopian tube, many barriers have been created evolutionarily in order to weed out the "weak". Getting into the vagina, the first obstacle is the acidic environment, in which a significant number of "fighters" die and lose their mobility, and only a small number manage to get into the mucous plug of the cervix, which has a comfortable alkaline environment that preserves their mobility, and "softened" by hormones favorable for fertilization. background.

Spermatozoa begin to move continuously towards the target at an average speed of 1-2 mm/hour. Special receptors help them choose the right direction for movement, which capture the pheromones produced by the egg. In fact, they move towards her by her "smell". So after 1.5 hours, on average, they find themselves in the uterine cavity, and after 3-6 hours they reach the fallopian tube.

It is important to note that every month ovulation occurs only in 1 ovary, and accordingly, the fallopian tube, into which the egg should fall, is in a state of functional readiness. Under the influence of estrogens, it is more expanded and relaxed, as if saying "the path is open." Plus the "smell" of the egg, which makes the spermatozoa crawl into it. By the way, semen contains various biologically active substances that help reduce the fallopian tubes and help the movement of sperm towards the egg.

In order for fertilization to occur, a sufficiently high quality of sperm is necessary, sperm motility is important. Ideally, there should be at least 50% motile, and in sufficient concentration - about 100,000-400,000 spermatozoa are needed to fertilize 1 egg. One misguided spermatozoon "is not a warrior in the field", and is hardly able to "pierce" the cells of the radiant crown and the shell of the egg, this is real teamwork. To do this, there are about ten special enzymes on the tip of the spermatozoon that help dissolve this "barrier". Only one will be able to penetrate, if a failure occurs and several sperm enter, the embryo will die due to genetic abnormalities.

Fertilization

And now the sperm penetrated the egg, fertilization took place, from that moment their joint work begins. The meeting of germ cells often occurs in the ampullar part of the fallopian tube, the process of penetration and fusion takes from 24 to 48 hours. Having united into one cell, called a zygote, the gradual division of cells and the movement of the future embryo through the fallopian tube to the body of the uterus begins. At this stage, natural selection also occurs - in the presence of damage to the genetic material, or in the presence of mutations incompatible with life, sexually transmitted infections and in the presence of some other factors, the zygote may die. With a favorable development of events, implantation occurs in the mucous membrane of the body of the uterus. This is a rather complex process, for which immune mechanisms are very important that ensure the interaction between the embryo and the uterine mucosa. The fact is that the embryo is no longer an egg or sperm, it differs from them genetically and immunologically, therefore the uterine mucosa must accept it and then the embryo will implant. It can be early, normal or late. On average, it occurs between 7 and 10 days after ovulation, but there are exceptions.

Statistical reference. The probability of embryo implantation depending on the day after ovulation:

• 0.68% on days 3-5;
• 1.39% on day 6;
• 5.56% on day 7;
• 18.06% on day 8;
• 36.81% on day 9;
• 27.78% on day 10;
• 6.94% on day 11;
• 2.78% on day 12.

Therefore, the highest probability of embryo implantation is the period from 8 to 10 days after ovulation, and after another 10 days you can see 2 stripes on a pregnancy test.

The likelihood of conception or the relationship of fertilization with sexual intercourse

A study was conducted that showed that the most favorable time for conception is 6 days prior to ovulation and the day of ovulation itself. If during these 6 days a woman had a single sexual intercourse, then the probability of pregnancy ranges from 8-10% on the first day of this interval to 33-36% on the day of ovulation. Also, the probability is highest 2 days before ovulation and is 34-36%.

When the study intervals were extended by 1 day in both directions (seven days before ovulation and the next day after it), it was found that the probability of conception on these days is almost zero.

The highest probability of conception was in women who had daily sexual intercourse for 6 days including the day of ovulation - 37%. Women who had sexual intercourse 1 time in 2 days had a chance of getting pregnant on the day of ovulation - 33%, and those who had 1 sexual intercourse per week - 15%.

The probability of conception depends on the mobility and life expectancy, the ability to fertilize sperm and eggs. The first live in the fallopian tubes on average 2-3 days, in rare cases 5-7 days, while the egg has a much shorter lifespan from 12 to 24 hours on average, up to 48 hours in rare cases. Nevertheless, there is evidence that the ability to fertilize both the egg and the sperm is about 24 hours.

So, given the above facts, completely healthy partners can only focus on a rather modest probability of conceiving a child - 20-25% in each menstrual cycle.

The lifespan of a spermatozoon- an important issue, especially relevant for people planning to continue the family. Researchers disagree on the lifetime of spermatozoa outside the body of a man: from 15 minutes - 2 days outside the female reproductive system to 8 - 14 days in the body of a woman.

In general, the entire life of the spermatozoon can be divided into 2 periods:

• Initially, the sperm cell is born and lives in the male body. It matures in the body of a man within 72 - 74 days. During this time, the sperm receives its individual chromosome set. However, in order to enter the egg, the sperm needs to be able to get to it, pass through the membranes of the egg without damaging its genetic material.
  Such abilities acquires when it passes through the epididymis. It becomes a full-fledged mature spermatozoon. A sperm cell that has lived in the body for more than a month becomes unable to fertilize the egg.
• When does a sperm leave a man's body?, his life begins in the external environment. The duration of this stage in the life of the male seed depends on many things: on the environment in which it is located, on the temperature of this environment, on the quality of the spermatozoon itself, on its chromosome set, etc.

Sperm life and temperature

Ambient temperature has a great influence on the life span of the seed. The most favorable temperature environment for the life of spermatozoa is 36 - 37 degrees Celsius. Temperatures exceeding this indicator adversely affect the life expectancy of the spermatozoon, its lifespan is reduced.

Men who are planning to conceive should not wear tight clothing and underwear, as such clothing can lead to overheating of the testicles. They should also avoid any other overheating.

Under the influence of low temperatures male spermatozoa are immobilized. But at the same time they retain their viability. This feature of spermatozoa is used to create sperm banks. Spermatozoa are frozen in special storage facilities, and later used for artificial insemination.

Sperm life and environment

Once outside the male body, the sperm cell enters an unfamiliar environment.

Various factors influence his life in this environment:

• temperature: too high or low temperatures adversely affect the viability and motility of the sperm, the optimal temperature regime for it is the temperature of the human body (36 - 37 degrees Celsius);
• light: bright light, especially sunlight, contributes to faster death of spermatozoa;
• acid-base balance of the environment: an alkaline environment activates the spermatozoon, and an acidic environment, on the contrary, reduces the activity of the spermatozoon;
• exposure to various synthetic compounds: for example, spermatozoa that have entered the condom will die faster, and various synthetic lubricants that are sold in pharmacies can also be negatively affected.

How to prolong the life of the sperm?

Some tricks can lengthen the life of the sperm:

• it is necessary to avoid exposing the male seed to too high temperatures: a man planning a conception should refuse to visit the bath, sauna, wearing tight underwear;
• do not use synthetic lubricants the synthetic substances contained in them can adversely affect life expectancy and activity;
• can't douche since it changes the acid-base balance in the reproductive organs of a woman and washes out the cervical fluid (it helps the sperm to move to the uterus);
• if it is necessary to save the spermatozoa for the bank, a too sharp drop in temperature should not be allowed, since such a decrease can cause a temperature shock and the spermatozoa will die, the ideal temperature conditions for working with fresh sperm will be 18 - 25 degrees (at this temperature, the speed of spermatozoa decreases, they spend less energy and, accordingly, live longer)
• in an effort to extend the life of spermatozoa, it is necessary to protect them from bright light, especially from exposure to sunlight;
• saving sperm for sperm bank, it is necessary to ensure that they are in a neutral or slightly acidic environment.

How long does a spermatozoon live in the air, in the uterus?

With ejaculation spermatozoa die quite quickly, as they are affected by negative environmental factors: temperature, humidity, light, acid-base reaction of the environment.

Spermatozoa live the least that did not enter the partner's vagina. According to studies, they die within 15 - 120 minutes. Those spermatozoa that have entered the uterus live much longer.

How long does a sperm cell live in a woman?

Sperms live longer caught in the reproductive organs of a woman. There they live and retain the ability to fertilize for several days. Some authors believe that the sperm in the female body can live 24 - 36 hours, other researchers talk about 8 - 14 days. Thus, fertilization can occur a considerable time after copulation.

An important role for the life of the sperm in the female body, the acid-base environment of the woman's vagina plays. For good sperm motility and viability, a slightly acidic environment is suitable. If a woman has any inflammatory diseases of the urogenital system, then the environment of her vagina becomes more acidic. In such an environment, spermatozoa move more slowly and die faster.

During intercourse a huge amount enters the woman's body, but only one of them is destined to merge with the woman's egg. What is the fate of the rest of the spermatozoa? They move into the uterine cavity very quickly, literally 1-2 minutes after intercourse, they enter the uterus, and after 2-3 hours they reach the extreme sections of the fallopian tubes.

Strongest and the motile sperm enters the egg. When the egg and sperm merge, the egg changes its properties - it no longer accepts other sperm. The rest of the spermatozoa die. Part of it flows out of the vagina along with the sperm and dies rather quickly in the air. The other part dies in the acidic environment of the vagina. Spermatozoa live longer if they enter the weak alkaline environment of the uterus and fallopian tubes. However, over time, these spermatozoa also die.

It is worth noting that the first to die are spermatozoa - carriers of the Y-chromosome. These spermatozoa, on the one hand, are more mobile, but on the other hand, are less viable than the carriers of the X chromosome.

Therefore, if sexual intercourse occurs just before ovulation, there is a high probability that a sperm with a Y chromosome will enter the egg. In this case, the woman will become pregnant with a boy. If sexual intercourse occurs a few days before ovulation, most likely, an X-chromosome carrier sperm will connect with the egg, and a girl will become pregnant.

How long does a spermatozoon live in air?

Sperm exposed to air lives on average from 15 minutes to 2 hours. This, of course, is a very short time. However, do not forget about it, especially for couples who are not planning a pregnancy.

If a couple wants to repeat sexual intercourse, the man needs to wash off all the semen from the penis. Otherwise, even a small amount of sperm can enter the woman's vagina and reach the uterus. In this case, the likelihood of an unwanted pregnancy is high.

Single spermatozoon, extracted from sperm, dies immediately, as it is deprived of the nutrients necessary to maintain its vital functions. These substances are found only in

Knowledge about the lifespan of a sperm cell can be useful for many couples: and those who are planning the birth of a child, and those who want to avoid unwanted pregnancies. Couples planning a pregnancy should follow the simple tips given in the article to ensure the greatest sperm motility and viability. Also, this knowledge will be useful to laboratory assistants involved in the collection of sperm and the creation of sperm banks.