What is the best way to not get pregnant. The most effective ways not to get pregnant

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Sexual activity is somehow connected with childbearing function Therefore, children are considered a natural result of sexual intercourse. But what can you do to avoid getting pregnant? After all, people do not always have sex in order to procreate. There are many methods of contraception. Which one to use, everyone must decide for themselves.

Method number 1 - is there any possibility of getting pregnant

Sometimes a woman makes a lot of effort to get pregnant, but because of individual features body, conception cannot occur in principle. This happens with the bending of the uterus, obstruction of the tubes, and other diseases. It is not so easy for many girls to get pregnant, and some will not be able to conceive a child at all.

Method number 2 - calculate dangerous days

The method is based on counting the days in which there is an increased risk of conception. During ovulation, which lasts 1-2 days, a woman's body creates ideal conditions for conception. The rest of the days are less dangerous. It remains only to find out on which days ovulation will take place. There are several reliable methods for this.

calendar method

Requires regular counting menstrual cycle throughout half a year. If the cycle is somewhat stable, this way protection suitable for use.

First you need to know the duration of the shortest and longest cycle.

  • Subtract 18 from the duration of the shortest cycle. For example, subtract 18 from 25. Therefore, from the 7th day of the cycle, the probability of conception increases dramatically.
  • Subtract 11 from the duration of the longest cycle. For example, subtract 11 from 30. Therefore, from the 19th day of the cycle, the probability of conception decreases sharply.
  • According to our approximate calculations, from the 7th to the 19th day of the monthly cycle, a high probability of conception remains.

Method for measuring basal temperature

Somewhat more accurate than the calendar method and requires regular measurements and calculations. In this case, it is necessary within long period to measure basal body temperature in the rectum. This is done in morning time immediately after waking up. It is known that before ovulation, the basal temperature is 36.6-36.9 degrees. At the time of ovulation, it rises by 0.3-0.4 degrees. Starting from the day of ovulation, you should start using barrier methods of contraception.

Intuition method

Less accurate than the previous two, and based on the objective sensations of the girl, such as pain in the ovaries, increased libido, the appearance of transparent discharge.

Ovulation Tests

In their principle, they are similar to pregnancy tests. The main difference is that tests must be done daily until ovulation occurs, when two strips are clearly displayed on the test.

Method number 3 - interrupted sexual intercourse

The method of interrupting sexual intercourse is one of the most common methods of contraception, which consists in the fact that during intercourse a man removes the penis from the vagina until the moment of ejaculation. The method has its disadvantages: some sperm may be present in the lubricant. In addition, with repeated contact, semen residues may enter from the head or urethra into the vagina.

Method number 4 - douching

It has been proven that spermatozoa die very quickly in an acidic environment. Douching the vagina with lemon juice, vinegar essence and other solutions is also a remedy for unwanted pregnancy. Like other methods of contraception, douching has its drawbacks - there is a risk of burning the vaginal mucosa, and the reliability of the method leaves much to be desired.

Method number 5 - more steam, less risk

According to some reports, overheating of the scrotum leads to a significant decrease in the viability of sperm. Having visited the sauna an hour or two before intimacy, a man's chances of conception are significantly reduced.

Method number 6 - water as a contraceptive

Popular opinion is that during sex in water, conception will not occur. This method of contraception is questionable, since water is not a substance that can harm sperm.

Method number 7 - the right choice of pose

It is believed that at the time of ejaculation, a woman should be in an upright position. In this case, a smaller amount of sperm will be able to get to the uterus. Indeed, most of the sperm will drain down, but the first portion of sperm is released under some pressure, so the risk of conception still remains.

Method number 8 - lubricant as a contraceptive

For the thrill of sensations and with a lack of natural lubrication in a girl, some couples successfully use artificial lubricants - lubricants. Lubricants and lubricants in themselves interfere with the normal functioning of spermatozoa, but if you apply a lubricant with contraceptive effect the chances of pregnancy are greatly reduced.

Method number 9 - condom

The condom is the safest contraceptive. In addition to contraception, it guarantees effective protection from dangerous ailments sexually transmitted. The only drawback of a condom is a slight decrease in sensations during intimacy. But are the more vivid sensations of contact worth risking health or getting an unwanted pregnancy?

Method number 10 - hormonal contraception

A good alternative to a condom is the method hormonal contraception, which consists in taking daily pills that block the production of mature eggs. Simply put, ovulation does not occur. 3-4 weeks after the end of medication reproductive function is being restored. Before you start taking it, you need to consult a doctor.

Method number 11 - intrauterine contraceptives

Intrauterine contraceptives (spirals) are inserted into the cervix, which reduces the chance of conception to a minimum. The spiral is introduced for a period of 2 to 5 years, while the probability of avoiding pregnancy is very high. Disadvantages of the method: probability ectopic pregnancy, the risk of provoking erosion or inflammation.

Method number 12 - emergency interruption of conception

It often happens that the one and only unprotected contact ends with conception. In this case, it is possible to interrupt conception with the help of special drugs that are guaranteed to cause the menstrual cycle, thereby interrupting conception. You need to use such a “killer” hormonal drug as little as possible.

Method number 13 - hormonal injections

This method of contraception is similar to taking hormonal pills. The main difference is that you do not need to take pills every day, one procedure is enough. The next one is due in a few months. Injections are best suited for women who have already given birth. The method also has a drawback - in order to conceive a child, you will have to wait for the end of the drug's action.

Method number 14 - hormonal implants

Implantation method hormonal implants similar to the method of hormonal injections, it has the same advantages and the same disadvantages. In addition, there may be side effects, which can be disposed of only after the expiration of the drug.

Method number 15 - female condoms

These tools include caps and diaphragms. various forms and sizes. They are not always convenient to use. Especially if you install and select female condoms on your own, without a gynecologist.

Method number 16 - lubricants, creams, tampons

Lubricants, creams and tampons containing spermicides, substances that stop the viability of spermatozoa, have a high degree of reliability. Means act within 1 hour after they are applied to the walls of the vagina.

Method number 17 - birth control candles

Contraceptive suppositories in their principle of action resemble lubricant creams. The guarantee of funds is 80%, the validity period is 30-40 minutes. Candles are a good alternative to hormonal drugs (if they are intolerant).

Method number 18 - combining several protection methods

For example, the risk of conception is reduced by 99% when using candles, creams, lubricants and caps together.

Method number 19 - a contraceptive patch

The effectiveness of this newfangled remedy is about 99%. The patch that prevents conception is glued to the stomach, buttocks or back. The effect of the patch remains for 1 week, then in the next 2 weeks new patches are glued, and during menstruation, it is no longer necessary to stick a contraceptive.

Method number 20 - abstinence

All the mentioned methods of contraception will not give a 100% guarantee, but there is a method that guarantees this - abstaining from intimacy. Before doing unprotected sex, you need to think 10 times how it can end, and is it worth it ...

How to prevent pregnancy during casual sex

The surest, cheapest, and easiest way to protect yourself from pregnancy and other casual sex problems is to use a condom. But if the act was unprotected, you need to use the means emergency contraception- drugs Postinor or Ginepriston.

If the question “what to do in order not to get pregnant” is still relevant for you, try folk remedies from unwanted pregnancy. These include coitus interruptus, douching, or washing away after intercourse. Creating an unfavorable environment for sperm in the vagina also helps in this regard. For example, after taking a hot drink after making love sitz bath with added solution mustard powder(based on 1 liter of boiling water 1 spoon of powder), a woman can be sure that she will not become pregnant. Heat is detrimental to spermatozoa.

In conclusion, we give the floor to the doctors. What do they say about ways to protect against unwanted pregnancy?

For some, the conception of a child is a welcome and long-awaited process. Other men and women try in every way to avoid it. What days can you not get pregnant? This question is asked by couples who use coitus interruptus as contraception or calendar method calculation. The days when you can not get pregnant will be described in this article. You will get the opinion of experts on this issue. You can also find out how these most non-fertile days are calculated.

What days can you not get pregnant? Medics answer

If you ask this question to a gynecologist, reproductologist or obstetrician, you will not get a clear and unambiguous answer. Days when you can not get pregnant, in their opinion, simply do not exist. Throughout the cycle, a woman remains likely to be fertilized. It's just that on some days it is maximum, while on others it drops to a minimum. Doctors say: you can never guarantee that pregnancy will not occur in a certain period of the cycle. There is an exception to every rule.

Physicians also note that female body very unpredictable. Quite often due to the influence external factors the representative of the weaker sex occurs hormonal disbalance. It is because of this that pregnancy can occur when you definitely do not expect it.

A bit of theory

To find out on which days you can’t get pregnant, you should have a fairly clear picture of conception. Even at school, teachers tell children about this in biology and anatomy lessons.

So, male body produces seminal cells - spermatozoa. They are capable of fertilizing the female body with every sexual contact. That is why men do not exist certain days when you can or cannot conceive a child. If the representative of the stronger sex is healthy, he is always fertile, of course, after puberty.

What can be said about a woman? What days are you sure you can't get pregnant? There is only one answer to this question. Pregnancy cannot occur when there is no egg to fertilize. After all, it is the presence of this gamete in the genitals of the fairer sex that leads to fertilization. Without it, pregnancy is simply impossible.

How to calculate safe days not to get pregnant?

Finding out which days you can not get pregnant is quite simple. It is necessary to know exactly the length of a woman's menstrual cycle and the stability of these periods. We can talk about regularity when, for at least six months, the duration of the cycle did not vary by more than 1-2 days. The rupture of the dominant follicle and the release of the egg occurs on average two weeks before next menstruation. This is precisely the peculiarity of the second phase. It always lasts the same amount of time. Whereas the first half of the period can normally last from seven days to three weeks.

To calculate on which days you can not get pregnant, subtract 10-14 days from the duration of the cycle. The resulting number will be considered the most fertile day. During this period, the gamete ready for fertilization is released. In this state, the woman's body is still about two days. After that, the probability of pregnancy gradually decreases and reaches its minimum by the beginning of menstruation.

What can be said about the first half of the menstrual cycle? During this period, sexual contact with quite highly likely can lead to conception. It is worth remembering that spermatozoa are able to stay in the uterus and vagina of a woman for about one week. Based on these data, a simple calculation can be made. Remember that a lot depends on the length of the menstrual cycle. So, for women with a period of 21 days in the first half, there is no safe time. If the cycle lasts 35 days, then its first 14 days can be called infertile.

period of menstruation

What days of menstruation can not get pregnant? If we take into account the physiology of a woman and the above method of calculation, then we can answer this question as follows. The first days of discharge can be called safe. However, this rule is only true for women whose cycle has a duration of 28 days or more. For women with a short period, even the days of menstruation are dangerous.

There is also an opinion that during bleeding it is impossible to get pregnant. This is because the discharge simply flushes out sperm and male gametes from the uterus and vagina. Also during this period, the endometrium is in the most unfavorable condition for implantation. Even if fertilization occurs, the fertilized egg simply cannot attach and develop further.

What days after menstruation can not get pregnant?

Concerning menstrual flow, you already know. Let's try to calculate on which days it is definitely impossible to get pregnant in one case or another.

  • In a three week cycle safe days can be considered the period from 10 to 21 days.
  • If your cycle lasts four weeks, then the absence of pregnancy is likely with intercourse from 1 to 7 days and from 18 to 28.
  • With a long cycle of five weeks, the safe days are the first 14 days, as well as the period from 25 to 35 days.

Summarizing

Many of the fair sex use the methods described above and try to find out which days you can’t get pregnant. Calculating the safe period is pretty easy. However, no one can guarantee you success.

Women say that misfires do happen. The reason for this may be hormonal failure. In this case, the cycle is shortened or lengthened. The ovulation period is similarly shifted. Also, the environment for the stay of spermatozoa can be quite favorable. In this case, they will remain in the woman's body for up to ten days. Statistics say that every third representative of the weaker sex, using this method contraception, turns out to be pregnant. Protect yourself properly. Health to you!

As soon as teenagers enter puberty, they become interested in the opposite sex. This is the best time to tell them in detail about existing methods contraception. ? The answer to this question should be known not only to the girl, but also to the guy. If none of the partners is yet ready to shoulder the burden of responsibility for the birth and upbringing of a new person, then it is important to go through an elementary educational program.

There are many ways to protect yourself today. These are hormonal pills, suppositories, intrauterine devices, the use of condoms.

A condom is the most reliable barrier, it is put on an erect penis and protects the mucous membranes of both partners. Young men are reluctant to use it, so often the responsibility for unwanted pregnancy is shifted to the girl.

The girl can use chemical contraceptives. These are vaginal creams, suppositories and tampons. They are inserted into the vagina just before sexual intercourse itself. Reliability is about 75-80%. And this must be taken into account when choosing this tool.

Modern mechanical contraceptives that release hormones when used are more reliable. They provide almost complete security. In Russia, two means are actively used: the NovaRing ring and the Eva patch. The first contraceptive is designed for one cycle. The ring is removed from the vagina on day 22, and a new one is inserted a week later. The patch is glued to any part of the body, the validity of one plate is a week. You can use the patch in the first three weeks of the month, on the fourth the body should rest. It will be impossible to make love at this time.

Another "female" alternative is hormonal pills. Available for sale a large number of similar drugs, but only a gynecologist is able to choose the optimal one that can reliably protect against pregnancy.

Intrauterine devices and sterilization at such a young age are not considered at all.

"Folk remedies"

Not all young people can publicize their desire, go to a gynecologist or a pharmacy in order to buy one of the listed contraceptive options. Therefore, adolescents are mainly interested in reliable advice on how not to get pregnant without contraceptives. There are several of them, the most useful ones can be adopted and used every time after unprotected intercourse.

  1. ? Arrange with your boyfriend, ask him to control the process and make sure that the sperm does not get into the vagina. Sending sperm past is within the power of any man. But it is important to take into account that even before orgasm, a small amount of sperm, along with lubricant, still gets inside. Therefore, along with this option, it is advisable to use the second tip.
  2. Immediately after intercourse, the girl needs to urgently go to the toilet and wash herself using any acidic liquid. It is best to use lemon juice diluted in water or highly diluted vinegar for this. If none of this is at hand, draw urine into the palm of your hand, moisten it with plenty of water thumbs and insert into the vagina. Such an action will stop the life of the sperm. This advice can be adopted by all those who are looking for an answer to the question of how not to get pregnant for the first time if you have finished.
  3. The easiest way is to learn how to find safe days. In the menstrual cycle of any girl there is a period when the egg "sleeps". Let's talk about this in more detail.

Safe days

Note! It is possible to calculate safe days only with stable and regular periods, when the body works like a clock and monthly cycle always about the same. It is useful to have a separate calendar and monthly mark the beginning of menstruation (the first day when the discharge begins) and their end. The calendar will immediately show the longest cycle and the shortest. The beginning of the countdown should be ovulation. It occurs, as a rule, on the 11th - 18th day after the onset of menstruation (everyone has different ways).

So how to calculate so as not to get pregnant? It is necessary to take the most short cycle, let's say it is 27 days, and subtract the number 11 from it (27-11=16). Then we take the largest menstrual cycle, let's say it is 29 days, subtract the number 18 from it (29-18 \u003d 11). It turns out that from the 11th to the 16th day of each month inclusive - this is the most auspicious time for conception. It is impossible to have sex during this period without full protection. If there is no desire to become pregnant, it is better to give up sexual activity altogether for this time. All other days until the 11th and after the 16th, by using the above methods, you can protect yourself from unwanted pregnancy.

Measurement of basal temperature

What to do for those who have irregular periods, how to calculate “safe days” in this case and how not to get pregnant after intercourse? Measure your basal temperature! This should be done immediately after waking up in the morning. The thermometer is inserted into the vagina, its readings are recorded daily. If the girl is healthy, the temperature will be approximately the same every day. But the day before the start of ovulation, it will rise by 0.2-0.4 degrees. This will be the starting point of the above calculations.

The natural result of lovemaking is the birth of a child. However, it is human nature to have sex not only for the purpose of procreation. Consider in this article the methods of contraception and their effectiveness.


It is quite effective (80-90%). It consists in calculating safe days". The maximum chance of getting pregnant falls on the period of ovulation - this is only a few days. On other days, the risk of conception is significantly reduced.

From the short one, you need to subtract the number 18 to get the day of the cycle, from which the most dangerous period begins. For example: 26 - 18 = 8, that is most likely conception begins on the 8th day of the menstrual cycle.
Then the number 11 should be subtracted from the longest period. For example: 30 - 11 \u003d 19, this means that the 19th day of the menstrual cycle is the last when there is a maximum opportunity to become pregnant. From the above example, it can be seen that pregnancy is possible from the 8th to the 19th day of the menstrual cycle, and the remaining days are considered “safe”.

douching

Spermatozoa die in an acidic environment. Therefore, douching with an acidic solution immediately after sex is one of the methods to prevent unwanted pregnancy. For this you can use lemon juice, vinegar essence diluted in certain proportions, fresh urine.

Many use "Miramistin", and other drugs.

But the method of douching is not very effective, since the spermatozoa are very mobile, and they can hide in the mucus of the cervical canal - this makes them unattainable.

Important!Frequent use of acidic solutions leads to burns of the vaginal mucosa, to dysbacteriosis, thrush.

The method of interrupting sexual intercourse is that the man removes the penis from the vagina immediately before ejaculation. The method is effective by 80-85%. But still there are some disadvantages:

  • spermatozoa are very "tenacious", so the method is valid only for the first sexual intercourse. The likelihood of getting pregnant increases with repeated intercourse, since the spermatozoa remaining on the penis penetrate the vagina;
  • penis lubrication contains a small amount active sperm , therefore, even before ejaculation, they can penetrate the vagina;
  • a woman is completely dependent on her partner who cannot always control himself and stop in time.

Use of high temperatures

High temperatures affect the viability of spermatozoa. Overheating of the scrotum can be obtained if you take too hot a bath, go to the sauna often, wear very tight swimming trunks and trousers. All this disrupts the process of sperm formation.

Therefore, in order for a man’s sperm to become partially “safe”, it is enough for him to spend several hours in the bath. Or take a hot bath before the planned sexual intercourse. Even a common flu with a temperature of 38-39 ° C worsens sperm viability by about 2 months.

This method is that sexual intercourse should end when the girl is in a vertical position. In the supine position, there are no obstacles for the penetration of spermatozoa into the uterus.

And if a girl stands on her feet or is in the “rider” position, then most of the seminal fluid will flow out, reducing the possibility of conception to a minimum.
This method is not very effective, since the first portion of sperm is released under pressure, so there is a possibility of pregnancy.

Reception protects against pregnancy by 96.5-97%. The pills block the production of mature eggs. talking plain language- Ovulation does not occur. Oral contraceptives effective if taken daily, do not skip and drink them at the same time.

It must be remembered that the pills are hormonal. It is important to consult a gynecologist so that he selects the most suitable for you.

Properly selected contraceptives do not have a negative impact on health, and within 20-30 days after the drug is discontinued, female reproductive function resumes.
Emergency contraception is used after sex or for 1-3 days after it. This method consists in preventing the fertilization of the egg or the attachment of the fetal egg.

This method is used after unprotected sex, if the condom broke, if the intrauterine device fell out, if the woman forgot to take more than three hormonal pills. The most reliable are drugs containing 1.5 mg of levonorgestrel. The tablet is drunk at a time or divided into 2 doses.

Important! It is often not recommended to take such drugs - they can cause hormonal disorder and cause interruptions in the menstrual cycle.

An intrauterine contraceptive is. It is a small T-shaped device that is inserted into the uterine cavity in order to prevent pregnancy due to mechanical impact. The efficiency of this method is 90-97%. The spiral is placed for 5 years, which is very convenient.

There are metal-containing hormonal spirals. The first variety includes copper, which, when oxidized, prevents the egg from attaching to the walls of the uterus. It also creates an impossible environment for the life of spermatozoa.

Hormonal coils release levonorgestrel daily, the endometrium changes, and implantation of the ovum becomes impossible.
Due to the presence foreign body in the uterus, the fallopian tubes contract more often, the eggs move faster, not having time to meet the sperm.

The disadvantage of using a spiral is that after its removal, reproductive function is restored in about a year.

Condoms are one of the most effective methods contraception (90-95%). It acts as a barrier to sperm entering the uterus. This method may be ineffective only if the condom breaks. To prevent this from happening, you need to use it correctly:

  • do not roll it out until putting it on the penis;
  • no need to check the integrity of the condom by inflating or filling it with water;
  • along with condoms, you should not additionally use oil-based lubricants - they reduce the strength of the latex.

The big advantage of a condom is that it protects against various infections and sexually transmitted diseases. And the disadvantages include a decrease in sensations during sex. Good protection against pregnancy and female condoms. These include a diaphragm, consisting of thin latex.

The effectiveness of the product depends on the correct size, which should clearly match the size of the vagina and cervix. A gynecologist can help determine the size.
female condom Such a cap, like a regular condom, prevents the penetration of spermatozoa into the uterus, but does not protect against infections.

They are chemical contraceptives. It can be candles, gels, creams. They have contraceptive, antimicrobial and antiviral action. They contain antiseptic substances that affect sperm and infections.

Spermicides are 79-90% effective. The acid of which they are composed is neutralized when interacting with an alkali. Therefore, if you plan to protect yourself with chemical means, you should not wash yourself with soap before and after sex.

Did you know? Spermicides have been popular at all times. AT Ancient Egypt for this, crocodile manure was used. The Egyptians mixed it with cotton and honey and used it before sexual intercourse.

During each sexual intercourse, it is advisable to put a new candle or a fraction of the cream.

Such drugs do not enter the blood, but have local action. Therefore, it is convenient to use them for nursing mothers.

Contraceptive patch

This method of contraception is one of the new. it is necessary to stick 1 time in 7 days on the shoulder blade, stomach or buttocks. Every week for 21 days it must be changed, and on the remaining 7 days it is not needed - this is the time of menstruation.

After its cancellation, it is necessary to wait some time for the body to restore reproductive function.

Did you know? In the USSR, the condom was called "Rubber Product No. 2". It was under this name that it was sold in pharmacies, and its price was 2 kopecks.

There are many methods of contraception. You need to listen to your body and choose the most suitable for yourself. If you use several methods at once, then the efficiency will increase significantly.

If you have any doubts, contact your gynecologist and he will help you choose the most effective and safe method of contraception for you.

The birth of a child is, of course, a great happiness. However, you must agree that pregnancy is not always desirable.

In this case, there are a huge number of contraceptives - from condoms and intrauterine devices before hormonal drugs. Today we will tell you about radical methods of contraception that help once and for all.

What is fertilization

Fertilization (or, what is the same, conception) is the process of fusion of the male sex cell (sperm) and the female (ovum). As a result, a single-celled embryo is formed, which is called a zygote. The zygote carries the genetic material of both the mother and the father.

Although only one sperm is destined to fuse with the egg, for successful conception participation is needed huge amount male reproductive cells. They secrete enzymes that “dissolve” the shells of the egg. The more spermatozoa - the more enzymes - the more likely successful fertilization.

Irrevocable contraception. female sterilization

female sterilization is radical method contraception, during which surgically patency is impaired fallopian tubes through which the eggs must pass. Thus, fertilization becomes impossible. Menstruation, sexual desire, the ability to have sexual intercourse and orgasm are preserved.

The first experiments on forced sterilization of women were carried out at the beginning of the twentieth century, in the USA, Canada, Sweden, and Denmark. Legislative acts were passed in these countries, according to which sterilization was subjected to persons with antisocial behavior and mental disorders. In Nazi Germany, from 1933 to 1945, 400,000 women were sterilized, including "racially inferior": Jews, blacks, Slavs.

Today, of course, this procedure is performed exclusively at the request of the woman. Moreover, Russian citizens are only allowed to be sterilized if they are over 35 years old or have 2 children, or if they have medical indications.

Undoubtedly, the effectiveness of this method is high. But you need to understand that not everything is so simple. Firstly, in some cases, an unwanted pregnancy may develop (worst of all - most often ectopic) due to spontaneous restoration of tubal patency. Secondly, if you suddenly want to have another child, you will most likely have to resort to IVF. Thirdly, it is possible to develop a number postoperative complications(for example, pain syndrome).

Thus, think carefully before deciding to sterilize. This method can be recommended for mothers with many children.

Vasectomy

Vasectomy is surgery, in which the ligation or removal of a fragment of the vas deferens in men is performed, through which the spermatozoa should have passed. As a result, azoospermia occurs (absence of spermatozoa in the ejaculate), and fertilization becomes impossible.

If you have any associations with castration, put them aside: vasectomy does not lead to aesthetic defects, does not interfere with the production of sex hormones, and does not cause problems in the sexual sphere.

After vasectomy, the development of chronic pain is also possible, but in general this method can be described as more positive in comparison with female sterilization. Because, unlike the latter, the consequences of a vasectomy are much easier to eliminate surgically (if suddenly a man decides to have another child). For this, there is a special technique - vasovasostomy, in fact - anastomosis of the ends of the vas deferens.