How many days can there be a cycle between menstruation? What cycle is considered normal?

Menstruation (or menstruation) is regular monthly bleeding from the genital tract of a girl/woman, which is considered part of the menstrual cycle. The essence of menstruation is that they complete it if fertilization of the egg matured in the ovary has not occurred. IN Everyday life Many people perceive the “red days of the calendar” as a certain process of symbolic “cleansing” of the female body, in particular the uterus and vagina, from everything superfluous and unnecessary.

The first menstruation - menarche - appears during puberty. As a rule, this happens at 12-15, more often at 12-13 years. The timing of the onset of menstruation depends on many factors: physical development the girl, her nutrition, previous diseases, etc. Approximately within 1.0 - 1.5 years after the start of the first bloody discharge regular monthly cycle, which is about 28 days, and bleeding lasts from 3 to 7 days; blood loss averages 50-70 ml.

About what kind of menstruation you have healthy woman We'll tell you in this article.

WHAT ARE NORMAL MENSURES?

A few days after the start of menstruation, the level of estrogen, female sex hormones, increases. At the same time, the transformation of the endometrium begins - the mucous layer lining the uterus from the inside. It grows, increasing in volume and thickness. At this time, the follicle with the next egg begins to mature in the ovary.

Approximately on the 12-14th day from the start of menstruation, ovulation occurs - the release of a mature egg from the ovary. This period is the most favorable for conception. In the ovary, in the place where the egg was released, the so-called corpus luteum, which begins to produce progesterone, one of the main hormones necessary for the development of pregnancy during its first three months. You can determine the moment of ovulation in the monthly cycle by measuring your basal temperature.

Then the egg, completely ready for fertilization, moves along fallopian tube to the uterus. She is programmed to ensure that after merging with a sperm, a human baby will grow over the next nine months. Therefore, during the cell’s journey, the endometrium, under the influence of the hormone progesterone, intensively produces nutrients for the initial nutrition of the egg with the embryo.

Fertilization occurs in the fallopian tube, then the dividing cell enters the uterus and is implanted in it, that is, immersed in it inner layer, where it begins to develop.

In the vast majority of cases, in the absence of fertilization, the monthly cycle does not end with pregnancy. Therefore, the endometrium, whose function was never realized, becomes unnecessary, and somewhere around the 14th day from ovulation (this is approximately the 28th day of the menstrual cycle), the level drops female hormones- estrogen and progesterone, - and the rejection of the inner layer of the uterus begins. Menstruation begins and stops around the 5th-7th day. In this case, in the first days the blood is bright scarlet, in the end it is dark, with a specific odor. The amount of blood lost is about 50 - 100 ml. With the end of bleeding, the circle closes, and then the entire process of the monthly cycle is repeated.

SIGNS OF PERIOD

  • bleeding from the vagina;
  • nagging pain lower abdomen;
  • swelling, heaviness and pain of the breast;
  • pain in the lumbar region;
  • irritability;
  • fatigue, heaviness in the legs;
  • dizziness, apathy;
  • sometimes - increased libido.

HOW MANY DAYS ARE YOUR MENSORS?

The menstrual cycle is the period from the first day of the onset of bleeding to the first day of the next. The normal menstrual cycle for healthy women is 20-35 days. The duration of monthly bleeding is from 3 to 7 days. You can track your menstrual schedule using a calendar, regularly marking the dates of arrival and end of discharge. There are also various special applications for mobile devices that can be downloaded on the Internet. The regularity of the monthly cycle is determined by the constructed schedule in the calendar. This indicator is very important for women's health, since it indicates proper operation ovaries.

How to find out how much blood is during menstruation?

Usually during this period we use special hygiene products- pads or tampons. Let's try to use them to determine possible blood loss. For example, a regular 4-5 drop pad absorbs up to 20-25 ml of blood. If in one day a girl changes her pad every 2-3 hours, it means she has heavy periods and needs to consult a specialist.

Scanty periods last less than 2 days and have a brown tint. Such brown periods appear due to the fact that the process of separating the remnants of the endometrium is very slow and the blood has time to clot, which causes this color. Scanty periods may indicate a violation of the second phase of the cycle and insufficient thickness of the endometrium. Among other things, this situation creates very real problems for the onset of pregnancy.

PROBLEMS WITH MENSURE - WHEN TO GO TO A GYNECOLOGIST:

  • the first menstruation appeared before 10 years;
  • at 15-16 years old, menstruation has not yet begun;
  • menstruation lasts 1-2 days or more than 7-8 days;
  • blood discharge is very scanty or very copious;
  • the monthly cycle lasts less than 20 days or more than 40;
  • strong pain lower abdomen during “critical days”;
  • bleeding between periods;
  • “those days” have not been around for a couple of months.

In all these cases, as well as in others associated with failure and delay of menstruation, it is necessary to consult a gynecologist-endocrinologist. In our medical center V certain days Accepted by a teenage gynecologist-endocrinologist.

With puberty, a monthly rhythmic process comes into a girl’s life, which is clearly repeated throughout her life until the onset of menopause. Norm menstrual cycle, i.e. its duration in days and number of cycles per year is the main indicator of a woman’s health.

How many days does the menstrual cycle last?

Average norm The menstrual cycle is considered to be 28 days. The normal range is 21 to 35 days. Everything that goes beyond this framework is already a deviation caused by any factors, external or internal. It is considered physiological when problems occur in teenage girls during the development of their female function or in women during the period of its attenuation.

The duration of the menstrual cycle and its normal flow may be disrupted under the influence of:

  • stress, work overload, overwork;
  • climate change, change of place of residence;
  • physical activity.

Deviations in the mechanism of the woman’s reproductive system also do not go away without leaving a trace; the duration of the menstrual cycle with normal rhythm is lost:

Menstruation cycle

Normally, the menstrual cycle consists of two periods separated by ovulation.

First phase

In the first half, which begins on the first day of menstruation, follicles begin to grow under the influence of FSH (follicle-stimulating hormone) and estrogen. Gradually, one of them breaks forward, a full-fledged egg develops in it, and the rest begin to disappear.

The level of the hormone of the first phase increases in parallel with the growth of the liquid vesicle, reaching its maximum value by the middle of the cycle, which forces the release of luteinizing hormone, which is a herald of the onset of ovulation.

Once using measurement basal temperature or when performing an ovulation test, a surge in LH is recorded, before the release female cage 24-36 hours remain. Exactly this favorable time for conception.

Phases of the menstrual cycle

Duration of the second phase

After the follicle ruptures, the second phase of the menstrual cycle begins, its norm is 14 days - a fixed value, the same for any woman. In the second phase, in the place of the ruptured vesicle, the corpus luteum begins to grow, producing progesterone. The latter controls fertilization, prepares the endometrium for the implantation of the embryo and helps its further growth and development.

If there is no fertilization in the second phase, the egg dies within 24 hours.

At the end of the second phase, the mucous layer of the uterus is shed, menstruation and a new menstrual cycle begin.

Errors in cycle time

We looked at what the norm is for a menstrual cycle that proceeds without deviations. But a number of women are faced with the problem of disruption of the regularity and duration of the menstrual cycle.

What are the dangers of deviations from the norm?

In such cases, shifts can occur at any stage, resulting in such atypical phenomena:

  • the follicle cannot develop;
  • a mature cell is unable to leave the ovary;
  • There is a deficiency of the corpus luteum, which prevents conception and attachment of the fertilized egg.

Duration of the menstrual cycle and its disruptions

Menstruation in such circumstances comes when they want. And therefore, it is difficult to say how many days the menstrual cycle normally lasts with such a deviation. This can be 17-20 days or last up to 40 days.

If there is a break between critical days ranges from 40 to 60 days, this is already a serious signal that requires contacting a gynecologist for a comprehensive examination and searching for the cause of the failure.

In such situations, determining the beginning of the menstrual cycle and how many days it should normally last is very difficult task. It is especially difficult for girls who want to track the moment of ovulation in order to conceive a child. Simple calculations as with the usual cycle duration will not help here.

How to avoid them

If doctors have determined that the problem is not pathological, but that there are no abnormalities in hormonal levels, then you need to reconsider your lifestyle:

Detection of ovulation in the menstrual cycle

It is better to try to calculate a favorable day for conception using ovulation tests. To find the starting day of the study, you need to select the shortest one from the last 3-6 cycles and subtract 17 from its value. As a result, we get a number indicating the first day of testing.


It must be carried out daily until detection positive result. Sometimes the procedure is repeated for up to 5 days and sexual intercourse during expected ovulation does not always result in fertilization.

In general, at the birth of a girl, thousands of follicle rudiments are already laid in her ovaries, which begin to actively develop with the onset of maturity. Research by specialists proves that not all monthly rhythmic periods end with the maturation of the female cell and its release from the ovary.

In a lifetime, only about 400 cycles end in ovulation, and only a few eggs are fertilized. Therefore, it is difficult to say specifically how many menstrual cycles per year normally end with ovulation. It all depends on the individuality of each female body and on many factors, both external and internal.

But, since determining the day the cell is released can play a significant role in planning pregnancy, in medicine there is sufficient quantity methods and means to help solve this problem.

In addition to measuring basal temperature with drawing up its schedule and ovulation tests, devices that calculate the desired time period using saliva are in demand. You can also simply listen to your feelings or monitor your character cervical mucus.

Ultrasound is considered the most reliable and truthful method today. This study is especially useful for irregular cycle duration or cycle disorders. Under its control, you can track the entire process of growth and development of the follicle, as well as confirm the release of the egg.

Conclusion

The normal menstrual cycle in days is 21-30. Normal cycle length allows you to correctly calculate the moment of ovulation to plan conception. Minor disruptions in duration are possible. If they occur frequently and for a very long time, you should immediately consult a specialist. This interferes with conception and may also indicate the onset of a disease or disorder. hormonal levels.

The nature of menstruation and its regularity are important indicators of women's reproductive health. The body reacts sensitively to any stress, so it is possible random deviations from the norm, which are not considered a pathology. However, if the disturbances are persistent, this may indicate a disease. It is convenient to mark the start and end days of menstruation on a calendar. This will allow you to find out the duration of the next cycle and not miss unusual changes. It is important to understand what processes occur between menstruation, when conception is possible, and why critical days occur more often or less frequently than usual.

Content:

Why is cycle duration calculated?

Processes in women's reproductive organs repeat every month, on average every 28 days. Due to the individual characteristics of the body, the cycle can be shorter (up to 21 days) or longer (up to 35 days). The main indicator of health is not so much the number of days in it, but the constancy of this indicator. If a woman gets her period regularly after 5 weeks or after 3 weeks, this is normal. But if they occur either after 35-40 days, or after 20-21, and this happens repeatedly, this is already a pathology.

  1. Prepare for the onset of menstruation, take measures to ease premenstrual syndrome(plan, for example, the load during critical days).
  2. Provide for the possibility of pregnancy in the middle of the cycle, increase attention to contraception.
  3. Take into account which days will be most favorable for conception and the onset of the planned pregnancy.
  4. Notice the onset of pregnancy and approximately calculate the day of birth.
  5. Plan a preventive visit to medical specialists (gynecologist, mammologist).

Having noticed persistent irregularities in the frequency of menstruation, it is necessary to consult a doctor in time to prevent early menopause or the occurrence of diseases of the uterus and ovaries.

What processes occur during the menstrual cycle

The processes occurring in the female reproductive system are directly related to the ratio of sex hormones that are produced in the ovaries. The cycle is conventionally divided into phases: follicular, in which the maturation of the egg occurs, ovulatory and luteal - the phase of the onset and maintenance of pregnancy.

Follicular phase

The beginning is considered the first day of menstruation. Its duration is different women ranges from 7 to 22 days (the duration of this particular phase determines whether a woman’s cycle is short or long). The phase begins with menstruation - the cleansing of the uterus from the endometrial layer that formed earlier. Menstruation occurs when fertilization of the egg does not occur.

By the end of menstruation, the pituitary gland begins to produce follicle-stimulating hormone, under the influence of which several follicles (vesicles with eggs) develop in the ovaries. Of these, one stands out, the largest (dominant), which grows to approximately 20 mm in diameter. The growth of the rest stops.

During the development of follicles, estrogens are intensively released, due to which a new layer of mucous membrane (endometrium) begins to grow in the uterus.

Ovulation

The follicle (the so-called Graafian vesicle) that has matured along with the egg bursts on days 7-22 (on average 14) of the cycle. At the same time, the hormone lutein is released from the pituitary gland, which promotes the formation of the corpus luteum from the ruptured membrane. Its purpose is to produce progesterone, which prevents the development of new follicles. Ovulation and progesterone production usually continues for 16-48 hours.

Luteal phase

It is called the corpus luteum phase. This temporary gland functions for approximately 12 days, producing progesterone. If fertilization of the egg occurs, the corpus luteum continues to function until the placenta forms in the endometrium. If pregnancy does not occur, the gland dies and menstruation begins.

Conception is most likely in those few days when ovulation occurs and a mature egg is released. By carefully observing the changes occurring in the body for six months, a woman can roughly predict when the “dangerous” days will come. The total duration of the luteal phase is 13-14 days and is practically unchanged.

Video: How to calculate the duration of menstruation and determine ovulation. Cycle phases

Causes of menstrual irregularities

In addition to fluctuations in the timing of menstruation, menstrual disorders also include the duration of menstruation less than 3 or more than 7 days, changes in the intensity of blood discharge (less than 40 ml or more than 80 ml for all days), lack of ovulation.

The causes of violations may be:

  1. Diseases of reproductive and endocrine organs. You need to know how to count your menstrual cycle so as not to miss the onset of the disease.
  2. Hormonal changes during natural age-related changes(maturing period, menopause). IN puberty The maturation of the ovaries is just beginning, so in the first 2 years, girls’ periods may be delayed by 2-6 months. Often, ovarian maturation is completed only during the first pregnancy. For many women, the cycle stabilizes after childbirth.
  3. Physiological processes during the period of recovery of the body after pregnancy and childbirth, during lactation.
  4. Hormonal imbalances after abortion.
  5. Hormone imbalance caused by stress, medications, sudden weight loss or weight gain.

The older the woman, the more likely occurrence of violations, as they accumulate possible reasons(number of births, abortions, consequences of gynecological and other diseases), the body ages.

Why does the cycle lengthen?

The reason for the increase in cycle length may be the lack of ovulation due to inadequate development of follicles. In this case, the corpus luteum does not form and progesterone levels do not increase. Under such conditions, under the influence of estrogens, the endometrium continues to grow until it begins to break down mechanically. In this case, the onset of menstruation is significantly delayed.

Another reason for lengthening the cycle may be the existence of the corpus luteum for too long after pregnancy has not occurred. This anomaly is determined using ultrasound.

Addition: The opposite situation is also possible. A woman experiences a delay in her period due to the onset of pregnancy, but when she comes to be checked by a gynecologist, it turns out that there is no corpus luteum in the ovaries, although it should be there and provide nutrition to the embryo. This indicates a threat of miscarriage. Required special treatment hormones.

Reasons for shortening the cycle

The cycle is shortened due to the fact that the corpus luteum dies earlier than usual, or follicle maturation and ovulation occur faster.

Often, deviations in cycle duration are the body’s response to the occurrence of extreme conditions life, when for health reasons or due to severe life situation bearing healthy offspring is impossible. For example, during the war, women lost their periods altogether.

Video: Duration of the menstrual cycle. Reasons for deviations

How is cycle time calculated?

The countdown starts from the first day of menstruation. And it ends on the last day before next menstruation. How to correctly calculate the menstrual cycle, taking into account the different number of days in each month, can be seen in examples.

Example 1. The woman had her previous menstruation on March 5, and the next one came on April 2. The duration of the cycle is 27 (the number of days starting from March 5 and ending on March 31) + 1 day (April 1) = 28 days.

Example 2. The previous menstruation was on September 16, the next one on October 14. The duration of the cycle is: 15 (from September 16 to 30) + 13 (in October) = 28 days.

Example 3. The previous menstruation was on February 10 (it was a leap year), and the next one came on March 6. The cycle is equal to: 20 (from February 10 to February 29) + 5 (in March) = 25 days.

Single deviations should not cause alarm; they can be considered the norm. But in case of long-term violations, it is necessary to undergo an examination to find out the cause.


Appear during puberty, and then repeat monthly throughout reproductive age up to 50, or even more years. Afterwards, it is still impossible to say exactly what type of woman’s symptoms are, because during the first two years the hormonal levels are normalized, that’s why. But at an older age, a woman already clearly knows how many days later her period comes.

The regularity of the menstrual cycle is a sign of the health of a woman’s reproductive system, therefore, in case of delays or too frequent periods, the cause of such a violation should be immediately determined.

In this article you will find out what interval between menstruation is normal, whether there is tolerance in the duration of the cycle and why there are short or long breaks between regulations.

How is the cycle calculated?

The most incorrect way to calculate the arrival date of the next critical days based on a calendar date is one that is very often used by inexperienced young girls. For example, menstrual flow started on January 3rd, and the lady is expected to have her next period on February 3rd, and is very surprised when she starts bleeding a little earlier.

In fact, the cycle is not tied to a specific date, it is characterized by a certain duration, which is individual for each woman, and the countdown of the new cycle begins on the first day of the next cycle. The number of days that have passed from the beginning of the previous menstruation to the beginning of the current one is precisely the length of the cycle. This parameter can vary within 21-35 days, the main thing is that menstruation should occur at regular intervals.

If the length of the cycle is different in each month, and the woman feels discomfort or even sharp pains in the lower abdomen, she should definitely consult a specialist.

How many days between periods is normal?

No specialist will give a specific answer to the question of what interval between periods is considered normal. This interval is individual for each representative of the fair sex. The average frequency of onset of regulation is 28 days; this is the cycle that is formed artificially when using contraceptives hormonal drugs. In life, not every woman can boast perfect health and a cycle duration of 28 days.

Experts allow a deviation in this indicator of +/- 7 days, that is, with a minimum cycle duration, menstruation begins every 21 days, and the maximum interval between regulations, which can be considered normal, is 35 days. During the specified period, a woman’s reproductive system must undergo many important processes aimed at preparing the body for possible pregnancy and gestation:

  • the dominant follicle matures;
  • the follicle ruptures and a mature egg is released;
  • a layer of endometrium sufficient for implantation of a fertilized egg is prepared;
  • The corpus luteum forms, secreting pregnancy hormones.

Each process listed above must be complete and complete, otherwise menstrual cycle disturbances occur - it is shortened or lengthened. If there are one-time failures, there is no need to panic, but if your periods begin to come irregularly in each cycle, then you need to seek medical help.

Normally, the intervals between regulations may be unstable in adolescents and in women during the period of aging reproductive function, after childbirth and when taking certain medications. If the cycle is disrupted, but all these factors are absent, then the cause may be pathological character. In addition, you should worry if or, as well as if their duration is too shortened or extended.

The following factors can change the interval between critical days:

  • sudden weight loss or weight gain before the start of a cycle, unbalanced diet, alcohol, bad habits;
  • stressful situations can increase the break between adjustments;
  • increased physical or psycho-emotional stress;
  • change in climate zone;
  • abortion, surgical interventions.

If, in addition to a change in the interval between menstruation, a woman feels bloating, nausea, dizziness or any other unpleasant symptoms, this may be a sign of inflammatory or infectious diseases, endometriosis, polyps, fibroids or cancerous tumors in the reproductive organs.

The interval between ovulation and the next periods

The length of the interval between menstruation is in most cases determined by the moment when ovulation occurs. The normal indicator is the release of the egg from dominant follicle on the 14th day after the start of regulation. If the cycle is 28 days, then 14 days should also pass from ovulation to the next menstruation, but a minimum delay of 1-2 days is allowed.

If it is typical for a woman to have menstruation every 28 days, but for some reason ovulation occurs earlier, for example, on days 11-12, then menstruation will also occur earlier on days 25-26. A similar situation may occur after successful completion of treatment for any pathology. In a similar way, the body shows that it has recovered and is ready to bear offspring. Rest in a hot climate zone or on mineral waters. If your period comes a little earlier than usual, there is no need to panic, it is important that the cycle does not become less than 21 days.

The second, luteal phase from ovulation to the arrival of the next regula lasts exactly 14 days, but the first part of the cycle is too susceptible to the influence of various factors, which leads to both slow and rapid maturation of the egg, and this entails a lengthening or shortening of the cycle as a whole . With age, the interval between menstruation increases, and closer to it it can reach 40-48 days; this is not a pathology if the figure is approximately the same from month to month.

Small cycle

Ovulation is very difficult process, for which the body first prepares, so new ovulation cannot occur immediately after menstruation. It takes a certain amount of time for the follicle to mature; for this reason, the first 8-10 days of the cycle are generally considered safe for pregnancy. It is on this principle that it is based calendar method protection.

But female body- this is a very subtle mechanism that can be influenced by almost any factor, so it is difficult to predict what impact a change in lifestyle or another quarrel with the boss at work will have on the range between menstruation. In theory, conception can occur on the 7-8th day of the cycle, when conditions are created for the rapid maturation of the egg, and such cases do occur, especially when the normal duration of the cycle due to individual characteristics body life for a woman is less than 21 days.

A minimal break between menstruation may occur in adolescence and during menopause, as well as due to hormonal imbalance. For example, when the level of progesterone increases significantly, the egg may not mature at all. The follicular phase, which usually lasts 2 weeks, can be shortened to 7 days. Most often, when the period between menstruation becomes less than 21 days, a lack of ovulation is detected. Diagnose similar anomaly possible by ultrasound, which is performed in different phases for a month.

Big cycle

If a woman’s period comes every 28-35 days, there is no need to worry; this cycle length is normal. A large gap between the regulators is observed in cases where the length increases follicular phase. More often similar phenomenon is explained by the peculiarities of the hormonal background, under which the body needs more time to mature the follicle and release the egg.

If your period comes after more than 35 days, you should consult your doctor, as this may be a sign of pathology. Closer to the period, the interval between menstruation may indeed increase, but gradually. This is due to changes in the process of egg maturation due to the withering of the reproductive function of the ovaries.

If they occur in women of reproductive age, a diagnosis of "" may be made. This is a condition in which menstruation takes 40 days or more to appear, caused by ovarian depletion. Such a pathology requires compulsory treatment. Additional symptoms of the disease are acne on the face and back, as well as increased level testosterone, which suppresses the process of egg maturation. The menstrual flow itself during oligomenorrhea is very scanty and more like daub.

The duration of the interval between critical days can be increased endocrine diseases, which lead to disruption of the secretion of hormones by the hypothalamus, pituitary gland and thyroid gland. If a woman is in reproductive age and also plans to have children, she mandatory you should find out the reason for both the lengthening and shortening of the cycle duration, and undergo treatment for the detected pathologies.

Menstruation is the shedding of the uterine lining and its removal from the body. Menstruation physically healthy girl has the appearance of bloody discharge, which is observed cyclically, after a certain number of days. The menstrual cycle of each woman is individual and proceeds with its own characteristics.

If one girl easily endures this period, then for another, “critical days” are a whole tragedy, which sometimes forces them to resort to pills.

However, any woman should navigate her own menstrual cycle. First of all, this gives an understanding of whether everything is okay with reproductive system. And besides, the ability to calculate the menstrual cycle helps to determine the exact date the beginning of your period and be prepared for its onset.

How to calculate the menstrual cycle? Not difficult. Every girl does this, at least intuitively. As a rule, women feel the approach of menstruation in advance based on signs of premenstrual syndrome or even based on the calendar.

However, not all phases of the menstrual cycle can be felt. The most important of them, ovulation, has to be calculated or measured.

Why should a girl know how to calculate her cycle?

  1. Monitor your health and pay attention to the first symptoms gynecological diseases. If the cycle is irregular for a long period, it is necessary to undergo examination to timely identify possible diseases.
  2. Increase the likelihood of conception if you want to get pregnant. For pregnancy, you need to know the date of ovulation, and it can be calculated by knowing the first day and duration of the cycle.
  3. For hygienic reasons. A properly calculated menstrual cycle will never come as a surprise. This will also help you spend your vacation comfortably, plan meetings, workouts, etc. in advance.

Many girls calculate the cycle to plan the so-called “ safe sex" But it should be borne in mind that the calendar method of birth control is considered the most unreliable, since it allows you to calculate only the most successful days for conception, but does not guarantee that ovulation will not occur earlier or later.

Methods for calculating the menstrual cycle

Many people believe that menstruation is calculated based on the number of days between menstruation. This is wrong. To calculate correctly you will need a pencil, a calendar and a little concentration. For at least three months, it is necessary to mark “critical days” directly on the calendar. And only then should we calculate the length of the cycle.

It is necessary to count the monthly segment of the cycle, including the first day of menstruation until the beginning of the next one. If menstruation starts on the same day of the month (for example, the 15th), the cycle is 30-31 days. In this case, the schedule shift occurs in March, because February is the shortest month and menstruation will arrive a few days later.

However, as a rule, regular cycle lasts 21 - 35 days. For this reason, menstruation never falls on the same dates. For example, if menstrual period less than 30 days, then the next menstruation will begin earlier, but the length of the cycle will not change in any way. It is more difficult if the menstrual cycle lasts more than 31 days.

In this case, the time of further menstruation will move forward several days. For example, the menstrual cycle is 35 days. In this case, the beginning of the next month is calculated as follows: 31 days of the current cycle plus 4 days - the beginning of the next one. Subsequent “critical days” will occur on the 9th, since 35 days must be counted from the beginning of the first cycle. There is no need to calculate the entire cycle several months in advance, because there may be deviations, which is a variant of the norm. This may be due to stress or acclimatization. But the absence of menstruation for more than 7 days may serve as a basis for probable pregnancy. There are several ways to calculate a cycle.

Calendar method

This is the oldest, but effective method. Its purpose is to know the exact date of the next menstruation. Its essence is simple: the immediate date of the onset of menstruation is marked on the calendar. This date will be the first day of the menstrual cycle. Doctors recommend considering the beginning of menstruation not as brownish discharge, but as the appearance of heavy bloody discharge.

How to count days suitable for conception or “dangerous” days: method one

If the cycle lasts the same number of days, then the highest probability of conception occurs in the middle of the cycle. It is necessary to divide the duration of the cycle by two. This will be the day of ovulation, and the probability of conception includes two days before it and two days after it. That is, if the cycle is 28 days, then 28/2 = 14. Ovulation occurs after fourteen days, counting from the first day of menstruation. And the probability of conception is high from the twelfth to the sixteenth day.

If the cycles last a different number of days, then you need to write down the duration of the shortest and longest cycles. Then take the number of days itself short period and subtract 18. This is the beginning of the fertile (or unsafe) period. Then you need to take the number of days most long cycle and subtract 11 - this is the end of the dangerous period.

For example, we take menstrual cycles calculated for six months: in January - 29 days, February - 27 days, March - 26 days, April - 29 days, May - 27 days, June - 26 days.

The smallest of them is 26 days. 26-18 = 6.

That is, if July 1 is the beginning of the cycle, then the probability of conception is lowest in the period from July 1 to July 7 and from July 19 to July 25. And from July 8 to July 18, conception is most likely.

This method helps to plan your pregnancy more effectively. However, it should be noted that these calculations are only suitable for women with a relatively regular cycle.