Menstrual cycle. The menstrual cycle in women: what is it, a description of each phase

reproductive system the female body is complex mechanism created by nature to continue the human race. From the moment of puberty to the onset of menopause, the purpose of the beautiful half of humanity is to bear and give birth to a child. In preparation for this event, unseen with a simple eye monthly processes, which are called the phases of the menstrual cycle.

First phase of the menstrual cycle

Myself cyclic period every woman is an individual phenomenon. Its beginning is considered the first day of menstruation, and the duration ranges from 21 to 35 days. The average ideal value is considered to be 28 days.

Start of egg growth

The first phase of the menstrual cycle is responsible for the beginning of the growth and development of the egg, it is called the follicular. The ovaries of a woman have a large number of rudiments of liquid bubbles. Together with the first day monthly bleeding those of them who will grow in the current month are outlined.

Estrogen production

Phase 1 of the menstrual cycle is a period where, under the influence of follicle-stimulating hormone, the production of estrogen gradually increases, which supports the development of follicles. Approximately on the 7th day of the cycle, one bubble significantly outperforms the others in all respects, this is for them something like a signal to stop growth and reverse development. And the leader of the race continues to grow the egg, reaching a limiting size of 20-25 mm in diameter. By this time, estrogen levels have reached their highest point which provokes the release of luteinizing hormone (LH), a harbinger of ovulation.

Features of ovulation

As soon as the growth of LH is fixed, on the way ovulatory phase, it is like a separation of the two halves of the cycle, which can be called the 3rd phase of the menstrual cycle, although rather it is a dividing line between them, located in its middle.

Ovulation is the shortest segment in a cycle of 24-36 hours, but the most significant. It is at this time that the mature egg breaks through the wall of the ovary and rushes into the fallopian tube, where it will meet with the sperm. If such a meeting does not happen, the cell dies in a day.

Second phase of the menstrual cycle

Once the egg has left the ovary, the second phase of the menstrual cycle begins. At the site of the rupture of the follicle, the corpus luteum begins to grow, producing progesterone, which helps fertilization occur, causes the endometrium to become loose, soft and thick enough to fertilized egg could easily penetrate into its wall.

luteal phase

The second segment is called the luteal phase of the menstrual cycle, what it is and why it is called that is simply explained. From fragments of the tissue of the liquid vesicle and vessels, special cells begin to grow, having yellow. Gradually, the cells turn into a temporary gland that produces lutein hormone, the hormone of pregnancy. The gland is called the corpus luteum, and since it plays a leading role in the second period of the cycle, the phase is also called the luteal.

Progesterone production

Phase 2 of the menstrual cycle is the process responsible for the onset and development of pregnancy with the help of progesterone produced by the gland until the placenta is formed, which takes over. In the absence of conception, by the beginning of a new cycle, the corpus luteum disappears.

Very detailed about the menstrual cycle

How long are cycle phases

Now let's return to the digital values ​​​​and analyze the phases of the menstrual cycle by day. We remember that the boundaries of this monthly phenomenon range from 21 to 35 days. Numerous studies have shown that its second half is constant and is 14 days. It can change its duration in the direction of decreasing or increasing only when it occurs pathological abnormalities in the female reproductive system. But the first phase - the value is different for each lady.

Now let's see how our girls feel about the first phase of the menstrual cycle and how many days it can take with a 28-day length:

• The first and second days are not encouraging, almost all of our ladies suffer from pain in the lower abdomen, and of course, bloody issues mood also does not improve, performance decreases, the usual rhythm of life decreases.
• From 3 to 6 days, the state and physical well-being begin to slowly stabilize.
• 7-12 days pass at good mood increased zeal for work usual things, appears sexual attraction and a lot of other positive emotions.
• 13-14 day - waiting for ovulation.

With a different duration of the rhythmic period, a similar table fits between 7-21 days.

And we are smoothly moving into the second phase of the menstrual cycle, and how many days it lasts, we have already determined as an established constant value - 14 days.

From 15 to 22 days, the state of health and mood is excellent. But sometimes at the end of this interval in some women after the fertilization has taken place, the moment the embryo is fixed in the uterus will be marked by the release of a few drops of blood and the appearance of a slight pain in the lower abdomen during the day.

If the egg dies without meeting male cage, then signs can be observed premenstrual syndrome from 23 to 28 days. They express themselves in irritability, frequent shift mood, tearfulness, tendency to depression, swelling and soreness of the mammary glands.

Table of phases of the menstrual cycle

If you link these days to the possibility of fertilization, then the table of the phases of the menstrual cycle looks like this:

• Starting from the first day of menstruation and up to day 11 with a 28-day period, fertilization is unlikely.
• Max Time for conception falls on 12-16 days. It is in this time period that if you want to get pregnant, sexual intercourse can be crowned with success, in the form of the birth of a new life.
• Well, if a joyful event in this moment did not happen, then from 17 to 28 days the ability to fertilize is zero.

But it should be taken into account that all these calculations refer to the regular menstrual process. In case of its violation, any outcome is possible. Yes, plus the individuality of each woman, so it’s not worth relying completely on the proposed tables, because reproductive system- a very cunning mechanism, capable of presenting unexpected surprises, in a life situation that seems to be calculated to the smallest detail.

To avoid disruptions in well-functioning work reproductive function, it is necessary that the phases of the menstrual cycle and the hormones that support them are in perfect harmony. Nature in this process thought through everything to the smallest detail.

If estrogen grows during the maturation of the egg, then progesterone has its minimum value. As soon as the first reaches its peak, the second immediately rises, taking its turn in the control of the following actions. Estrogen will not increase by the middle of the cycle, there will be no LH surge, ovulation will not occur, there will be no corpus luteum, there will be no one to produce the hormone of the second phase.

The slightest violation in this complex scheme of interaction leads to violations that prevent the conception and birth of a baby.

Most often Negative influence hormone function is influenced by external factors. Therefore, to keep your menstrual cycle running like clockwork:

• try to avoid stressful situations;
• observe the regime of work and rest;
• review your diet, eat healthy foods rich in vitamins and minerals.

In case of occurrence internal causes in the form of gynecological diseases, do not try to cope with the problem on your own, for this there are enough qualified doctors capable of as soon as possible save you the trouble.

Third phase - ovulation

Women's cycle consists of two phases, in the first the egg matures, and in the second the wound heals from the rupture of the follicle or conception occurs. The normal course of processes is controlled by the hormones produced. The 3rd phase of the menstrual cycle is considered to be ovulation, the release of cells, when conception is most likely. A girl should keep a calendar - a table where to mark the beginning of menstruation every month. With it, you can calculate the day of ovulation and control the normal course of the cycle.

Menstrual cycle- these are changes that occur in the genitals of a woman at approximately equal intervals of time.

What is the length of the menstrual cycle?

The normal length of the menstrual cycle is 21 to 35 days. The countdown of the menstrual cycle starts from the first day of bleeding.

Phases of the menstrual cycle and the hormones that regulate them

The menstrual cycle is divided into two phases, between which ovulation occurs.

The first phase is called follicular. It is in this phase that the follicle develops, from which the egg will be released, which can then turn into developing fetus and finally the child. It starts on the very first day of the onset of menstruation ( menstrual bleeding) and ends when ovulation occurs. It takes about half of the entire cycle. Special cages in this phase, the sex hormones estrogens are produced. Throughout follicular phase the menstrual cycle, the basal body temperature of a woman, as a rule, is kept below 37 degrees. The temperature must be known to clarify the moment of ovulation - at the time of ovulation, the basal temperature will drop sharply.

The next phase of the menstrual cycle - luteal, or the corpus luteum phase. The corpus luteum is formed in the ovary at the site of the released egg. This phase occurs immediately after ovulation and lasts as long as the yellow case exists, that is, on average, about 12-14 days. The main task at this stage is to maintain the balance of the hormones estrogen and progesterone, which the corpus luteum secretes to prepare the body for possible pregnancy. In this phase, the basal body temperature can stay at 37 degrees, and then, before the onset of menstruation (menstrual bleeding), drop sharply.

Ovulation- release of a mature (ready for fertilization) egg from the follicle to abdominal cavity with subsequent advancement through the fallopian tubes to the uterus itself. In the body of a woman by the time of puberty, approximately 300-400 thousand eggs are stored. All of them are in the ovaries from birth and are laid in the womb. The first ovulation occurs a little later than the onset of puberty, the last - after the extinction menstrual function, with menopause. During pregnancy, ovulation also does not occur, but after the birth of the child, it is restored.

Establishing the moment of ovulation is of interest mainly to those women who want to get pregnant, since the possibility of pregnancy exists only in certain days: 3-4 days before ovulation, during ovulation and 1-2 days after it.

Fig.: Phases of the menstrual cycle

Periods (phases) of the menstrual cycle

In each menstrual cycle, a woman's body prepares for pregnancy. The menstrual cycle can be divided into several periods (phases).

The most common menstrual cycle is 28 calendar days. However, for each woman it is strictly individual; it is normal if it fits in the interval from 21 to 35 days. The main factor is its constancy throughout reproductive period, allowable deviations are no more than 3 days. An important indicator also serves as the amount of discharge and the woman's well-being during this period. Any changes normal rhythm, signs of malaise are the reason for going to the doctor, as they may well be the first signs of the disease.

menstrual period of the cycle

The functioning of the female reproductive system is subject to four main periods. The first of them is menstrual, it is the most painful, it is at this time that spotting is observed. His normal duration is 3 to 6 days. At this stage, there is a rejection and expulsion of the inner lining of the uterus - the endometrium, along with an unfertilized egg. Thus, the first day of bleeding is the beginning of the menstrual cycle.

Follicular period of the cycle

Then follows the follicular period, characterized by the cessation of secretions. At this time, an increased synthesis of hormones from the pituitary and hypothalamus begins, which affect the ovaries. The main one is follicle-stimulating hormone (FSH), which causes intensive growth and development of several follicles. The ovaries, in turn, produce the sex hormone estrogen; its significance is to stimulate the renewal of the endometrium and prepare the uterus to accept the egg. This stage lasts about two weeks and ends due to the release of hormones into the blood that suppress the activity of FSH.

Ovulation

The ovulation phase begins, that is, the release of a mature egg from the follicle. As a rule, this is the largest of them. This contributes sharp rise luteinizing hormone (LH) levels. The egg enters the lumen of the fallopian tube and begins its movement towards the uterus, while waiting for fertilization. The duration of her life does not exceed two days, therefore, to increase the likelihood of conception, it is necessary that the sperm is already in fallopian tube. In the uterus at this time, the process of preparing the epithelial layer continues.

luteinizing period of the cycle

The final period of the menstrual cycle is luteinizing. Its duration, as a rule, does not exceed 16 days. At this time, in place of the follicle that the egg left, a special temporary gland is formed - the corpus luteum. It produces progesterone, designed to increase the sensitivity of the endometrium, in order to facilitate the introduction of a fertilized egg into the uterine wall. If implantation does not occur, the corpus luteum regresses and progesterone levels plummet. This causes destruction and subsequent rejection of the epithelial layer, the cycle closes.

Phases of the menstrual cycle

First phase (follicular, or egg development) Day 1-5. Menstruation. Typically, menstruation lasts from 2 to 7 days, with an average of 5 days. During this phase, the lining of the uterus (endometrium) is shed and menstruation begins. Uterine contractions at this point may be accompanied by pain in the lower abdomen. Some women have short periods (eg 2 days), while others can last up to 7 days. Bleeding may be profuse and spotting. In the first half of the menstrual cycle, a follicle grows in the ovary, where an egg develops and matures, which then leaves the ovary (ovulation). This phase lasts about 7-21 days, depending on many factors.	Ovulation Day 14. Release of the egg. Usually ovulation occurs from the 7th to the 21st day of the cycle, more often in the middle of the menstrual cycle (approximately on the 14th day in a 28-day cycle). After leaving the ovary, the mature egg moves to the uterus through the fallopian tubes.	Second phase (formation of the corpus luteum) Day 15-28. Thickening of the inner lining of the uterus. After ovulation, the ruptured follicle transforms into the corpus luteum, which produces the hormone progesterone.

Protection during intercourse often becomes a difficult issue for partners. Condoms are not suitable for everyone due to allergies or hormonal contraceptives due to side effects.

Spermicidal ointments are not effective enough, and there are many contraindications for spirals. Partners often resort to natural way protection - the calendar method, which is directly related to the maturation and release of the egg.

Egg release

The calendar method is based on the calculation dangerous days in the woman's cycle. To determine them, you need to know the most important day - the release of a mature egg, or ovulation. It is during these days that you can become pregnant, because female germ cells do not live long.

Ovulation usually occurs in the middle of the menstrual cycle and divides it into two phases. With an ideal cycle of 28 days, the release of the egg from the ovary occurs in two weeks. In this case, the period from 5–6 to 17–18 days will be dangerous.

But not all women have an organism that works with such accuracy, and sometimes it happens that the egg matures earlier.

Ovulation shift

Early ovulation is not uncommon even with normal, regular cycle. It's just that most women do not feel the process of the release of the egg and do not know whether it happened earlier or later than usual.

However, some suffer during this period from severe soreness and discomfort in the lower abdomen. This state is called mittelschmertz. In this case, one can suspect that there was an early maturation of the germ cell and make sure additional funds protection.

Also, the release date of the egg is known to those who regularly monitor basal body temperature. Its increase will definitely indicate that ovulation happened earlier.

The reasons

Why does ovulation sometimes occur earlier? Most often this happens for the following reasons:

1. Hormonal disbalance. The release of the egg is regulated by many hormones and not only sex hormones. The reproductive system of a woman is sensitive to any changes in metabolism.
2. Accompanying illnesses. They often cause late ovulation or its absence, but sometimes the opposite situation happens - the release of the egg on the 7-10th day.
3. Severe stress, change of time zone, regime or climate. All these factors affect general state woman and her reproductive system.

Do not forget about short menstrual cycles. If a woman's period begins after 21 days, then she will ovulate on the 9-10th day.

Many people are concerned about the question of whether the release of the egg is possible for 5-7 days. This phenomenon is unlikely and is usually associated with some serious hormonal disorder or double ovulation within the same menstrual cycle. But the situation is quite different with the possibility of becoming pregnant during this period.

Probability of pregnancy

When using the calendar method, some women do not take into account one extremely important fact: ovulation and conception can significantly lag behind each other in time. And if the release of the egg on day 5-7 healthy woman happens quite rarely, then you can get pregnant these days with ease. Why is this happening?

The fact is that spermatozoa in a woman's body can live for a long time, up to 7 days. And at the same time, their ability to fertilize the egg decreases slightly.

If unprotected intercourse occurred on the 7th day, then even a shift in ovulation is not required for conception to be successful. Therefore, it would be wrong to say that a woman became pregnant on the 7th day of the cycle, most likely this happened a little later. However the exact date conception cannot be indicated even by the most experienced and qualified doctor.

And if a woman with a normal or short cycle really had early ovulation, then even sex during menstruation will be dangerous for her if other methods of protection are not used.

That's why calendar method belongs to the most unreliable means of contraception. It works only under an ideal cycle and under the condition full health women. But even in this case, the slightest hormonal fluctuation can cause an early release of the egg and an unplanned pregnancy.

Confirmation of pregnancy

If unprotected intercourse was on the 5-7th day and after that there is a delay in menstruation, pregnancy should first be suspected.

To confirm or exclude it, you must use a special test that determines in the urine special hormone- chorionic gonadotropin. Such indicator tests are freely sold in pharmacies and are available to every woman.

If the release of the egg really happened earlier, then the conception did not occur at the usual time. And this means that by the first day of the expected delay in the level chorionic gonadotropin almost all tests will respond, even the most insensitive ones.

However, if the indicator shows a negative result, you should not relax. Perhaps fertilization was still in the middle of the cycle and the hormone level is still too low. It is recommended to repeat the procedure after 2-4 days and it is better to use tests from different manufacturers.

The most reliable method for determining pregnancy is the detection of human chorionic gonadotropin in venous blood. It is performed in laboratories and is informative even before the delay of menstruation.

Treatment

By itself, the early release of the egg does not threaten the health of the woman. However, it leads to unplanned pregnancies if the couple practices the calendar method of contraception. Or vice versa, because of such a violation, it is possible to be treated for infertility for a long time and to no avail, because the main attempts at conception will not be carried out during the period when fertilization is possible.

Does this condition need to be treated or can medication be dispensed with? This issue remains controversial. First of all, you need to find out the reason early ripening eggs. If this is a consequence of a dishormonal disease or a lesion of the reproductive system, then treatment is necessary.

But if such a violation of the menstrual cycle occurs under the influence external factors– stress, lifestyle changes, concomitant diseases, it is enough just to endure for a while, and normal cycle will recover on its own.

Usually, with such complaints, the gynecologist offers the patient to undergo a standard examination:

• General blood and urine tests.
• Determination of the hormonal profile.
• Ultrasound examination of the pelvic organs.
• Endocrinologist consultation.

According to the results comprehensive examination The question of the need for drug therapy is individually decided.

Hello! What should every woman know about her monthly phenomenon, laid down by nature? In the material - "The menstrual cycle in women", there are detailed answers to many important questions.

Feature of the female body

What is menstruation? Once a month, the uterus builds up a new endometrium, or lining, in preparation to receive a fertilized egg. When it is not there, the uterus begins to reject the lining.

menstrual period begins in girls when they are 11-14 years old and continues until about 50 years of age in women. Allocations become irregular at the age of 39-51 years, then they stop completely.

Start this natural phenomenon can make the girl anxious. In girls, bleeding may also be irregular at first. In a year everything will be back to normal.

Norm is 21,28,30 days. menstrual cycle confirms that the girl is healthy, developed and able to have offspring.

Women's cycle can lead a girl to pregnancy even from casual intercourse. Mom has to prepare her daughter for adulthood so that there is no trouble.

What is the menstrual cycle? A cycle is the period from the first day of bleeding to the first day next bleeding.

Cycle duration:

• medium - 28 days
• short - 21 days
• long - 35 days
• in adolescents it is not uncommon - 45 days. This is normal, then everything will be fine.

If you notice violations of the menstrual cycle, that is, it lasts more than 7 days, then you should consult a doctor. Perhaps he will prescribe treatment.

Cycle control is provided by hormones: estrogen and progesterone. What it is? These are the most important women's.

• Estrogen promotes the growth of the endometrium in the uterus.
• Progesterone is formed in the middle of the cycle, that is, after ovulation.

Both hormones prepare the uterus to receive a fertilized egg.

The middle of the cycle in women, what is it?

Approximately in the middle of the cycle in the female body, an egg matures, capable of fertilization, that is, ovulation occurs. If you are planning a pregnancy, then at this time female body ready to conceive a baby. How to determine this moment by day.

With a cycle of 28-30 days, ovulation occurs on the 14-15th day, if you count from the beginning blood secretions.

Sexual intercourse these days most often ends in pregnancy. Buy tests to determine the maturation of the egg. Testing should be done 24-48 hours before ovulation. If you do not plan to have children, then these days are considered the most dangerous.

But testing can fail because there are many various factors which can affect the duration of the cycle. You can calculate the phases of your menstrual cycle yourself if you measure your basal body temperature daily. Some women count these days for conception, while others - on the contrary, so as not to become pregnant.

1. Take a regular thermometer. Early in the morning, not getting out of bed, not doing sudden movements(this is important!), insert it into the rectum.
2. Hold there for 7 minutes.
3. Record your testimony.
4. Based on daily readings, draw a graph. In the top line, indicate the days of measurements, on the side - basal rate. At the junction, put points, which then connect with a straight line.

When does this process start?

On days when the temperature rises sharply, ovulation occurs.

It is important for every woman to know the phases of the cycle so as not to make a mistake in the calculation. Cycle phases, what are they? These are important periods between periods.

• First phase- follicular (the first phase, how many days does it last? 3-4 days);
• Second phase- ovulation;
• Third phase- luteal.

Follicular gives to the beginning of the formation and maturation of the egg. Ovulation - designed to perform an important female function- conception.

What happens in the second phase?

In the first phase of the cycle, the temperature is around 36.8°C. 1-2 days before ovulation, there is a decrease literally by a fraction of a degree. Then the indicator begins to grow within 3 days and remains at such indicators until the end of the second phase (37.0-37.5 ° C). The body is preparing for pregnancy.

Attention! Any stress, malaise, alcohol, bad habits can change your schedule and ovulation may occur on a different day, and then unwanted pregnancy. What happens to the body if fever does it last for two weeks? Congratulations on your pregnancy!

Average duration the second phase of the cycle, what does this mean for a woman? Within 4-6 days, you can conceive a child.

The luteal phase takes place in two ways:

• with a fertilized egg;
• or without it, if it was not fertilized;
• if conception has occurred, then the corpus luteum begins to be produced, which actively releases the hormone lutein. It is he who will support and "feed" the egg.

What keeps a woman from aging

These are hormones. The performance, attractiveness and mood of a woman often depend on them. In addition, the production of hormones changes almost every day during the process of hemorrhage, which is why women's moods change so often.

It is important to know the days of the cycle, the description of which will help you to know yourself better. In 1 day the uterus throws out the endometrium that has served, that is, bleeding begins. A woman may experience malaise, pain in the lower abdomen. To minimise pain, you can take "No-shpu", "Buscopan", "Belastezin", "Papaverine".

On day 2 starts heavy sweating. On day 3 the uterus is very open, which can contribute to infection. On this day, a woman can also become pregnant, so sex must be protected.

From day 4 mood begins to improve, efficiency appears, as menstruation is nearing completion.

What is the cycle by day in the second half? Days starting 9th to 11th day considered dangerous, you can get pregnant. They say that at this time you can conceive a girl. And on the day of ovulation and immediately after it, it is suitable for conceiving a boy.

On day 12 increases the libido of women, which entails a strong sexual desire.

When does the second half start? From day 14 when the egg begins to move towards the male principle, ovulation occurs. On the 16th day a woman may gain weight as her appetite increases. Until 19 days the possibility of getting pregnant remains.

From day 20"safe" days begin. What " safe days"? These days, the possibility of getting pregnant decreases.

Many women ask the question: is it possible for a woman to get pregnant before her menstrual cycle?

The probability is small, but no one can give a complete guarantee. The period of menstruation can change under the influence of many factors. No woman has an even cycle throughout her life. It can even change colds, fatigue or stress.

Many doctors warn that the body is able to “give out” repeated ovulation, so even 1 day before menstruation, you can conceive.

The female cycle by day, what happens these days, every woman should know, because it will show when you are ready to conceive, when you are passionate or vice versa - cold, why your mood changes so much.

sexual cycles

When you hear - the ovarian-menstrual cycle, it is the cyclical secretion of gonadotropin that is established in the body. The sexual cycle includes normal process occurring in the ovaries under the influence of hormones, and following it - menstruation.

Its duration is on average 28 +/- 7 days. What interval between periods is considered normal? If fertilization does not occur, then as soon as this cycle ends, the period of a new cycle begins. How long does it take? The interval between periods, the norm is from 21 to 35 days. But it also happens differently. Get a small calendar where you will celebrate the first day of the appearance of discharge.

It is worth noting that 14 days should elapse between ovulation and the next menstruation, but deviations of 1-2 days are possible. If you notice that you are too short or too long cycle, then you should consult a gynecologist to find out the reasons.

Violation of the cycle may indicate diseases of the genital area. When does the lengthening of the cycle begin? The cycle can only be lengthened after 45 years, as changes occur in the process of maturation of the egg.

Sometimes a woman may notice spotting even after menstruation. This should not be!

A drop of blood can only be released at the time of ovulation. If you notice sudden discharge, do not treat yourself - consult a doctor immediately!

Phases of the ovarian-menstrual cycle. Titles:

• Menstrual (desquamation phase)
• Postmenstrual (estrogenic, proliferative, reparative, or follicular)
• Premenstrual (progestin, luteal, secretory phase preceding pregnancy).

menstrual phase lasts an average of 4 days. The first day of the cycle is the beginning of endometrial rejection. These days, progesterone is absent, and estrogen has not yet formed.

Postmenstrual phase- begins on the 5th day of the ovarian cycle, ends 1-2 days after ovulation. Ovulation occurs in the middle of the cycle. In this phase, the growth and development of follicles occurs. During the development of the follicles, a large amount of estrogen is produced.

premenstrual phase lasts 12-14 days. High level progesterone these days creates favorable conditions for implantation of the embryo.

The graph shows the period of menstruation when you can get pregnant.

First menstruation in girls

She must go through all the stages of her growing up with her daughter, including the beginning of menstruation. First of all, it is necessary to explain what menstruation is in girls. The simplest explanation is that this phenomenon is inherent in nature and there is no need to be afraid of it. Be sure to explain - what is the duration of the menstrual cycle.

It is important for a girl to know the phases of menstruation, because in the middle of them a girl can become pregnant, which is very undesirable for an immature organism. Which phase is considered the most dangerous, every teenager should also know about it.

About how menstruation occurs, it is written above on the test. This process is the same for both an adult woman and a girl. But if adult woman already knows what symptoms precede it, then the teenager must be clearly explained.

Before the onset of menstruation, there are such phenomena: