When will the child be born if conceived. Pregnancy calendar is a useful feature

In this article:

A pregnant woman often worries about the day of her birth. She wants certainty in anticipation of her baby. Usually, when a woman first finds out that she is pregnant, one of the main and frequently asked questions is the day the baby is born. Namely, how to determine the date of birth.

The duration of pregnancy is not nine months, but 280 days, which is 10 lunar months. There are several common ways in which you can determine the approximate date of birth of the baby. But it is approximate, since it is almost impossible to determine the exact one. The day of birth is determined with an accuracy of one or several weeks. Since spermatozoa can remain alive in the female body, retaining the ability to fertilize for several days, knowing the exact date and month of conception, the exact day of delivery cannot be determined anyway.

How to determine the date of birth of a child by the day of ovulation and the date of conception

By the number of conception, the day the baby is born is not difficult to determine. As a rule, a woman's body is capable of conception only during the period of ovulation. The duration of the menstrual cycle is approximately 28-35 days. And in the middle of the menstrual cycle, ovulation occurs. If you know the calendar date of your ovulation, it is quite easy to calculate the day of birth. Many women feel their ovulation.

During its period, aching and stabbing sensations appear in the lower abdomen. Sexual desire becomes stronger, and the amount of vaginal discharge increases. Sometimes the discharge can be spotting bloody, but not strong. Only during this period can conception occur. Ovulation can be accurately determined by ultrasound. Without knowing the calendar date of your ovulation, you need to calculate the middle of the menstrual cycle.

For example, if the duration of the menstrual cycle is 28 days, then approximately on the 12-14th day of the cycle, ovulation occurs. To this day you need to add 280 days. Thus, the approximate date is calculated from the day of conception. This method will be most accurate in cases where there was only one sexual intercourse during the menstrual cycle.

How to determine the date of birth by ultrasound

On early dates pregnancy (up to 12 weeks), this significant day can be determined using ultrasound. Gynecologists consider this method the most accurate of all (but only for a short time). According to the results of ultrasound, the calendar date of the onset of labor is set at a later date. The gestational age is determined by the size of the limbs and the head of the fetus. But if we take the conclusion of such an ultrasound examination as a basis to determine when the birth will begin, then the date will turn out to be completely inaccurate. Because every baby in the womb develops differently.

It is considered the norm when a child is born weighing 3 kg. But if a child was born weighing 5 kg, this is also normal. Only in this case, the fetus develops faster, and the day of his birth, according to the conclusion of the ultrasound of the second and third trimester of pregnancy, is set 2-3 weeks earlier than the present date. And with a slower development of the fetus, on the contrary, the period is set a few weeks later. That is why it is possible to trust ultrasound to determine the day when labor begins, only for periods up to 12 weeks.

How to determine the date of birth of a child by the day of the last menstruation

In order for the doctor to determine the gestational age, he must be told the date and month when the first day of the last menstruation began. From this day, the countdown begins and the duration of the menstrual cycle is calculated. To determine the baby's birthday, gynecologists use the Naegele formula.

According to this formula, it is calculated according to the following principle: subtract 3 months from the calendar date of the first day of the last menstruation, then add 7 days to the resulting number. For example, the first day of your last period was April 3rd. Subtracting 3 months - we get January 3. And adding 7 days to January 3, we get January 10. This will be the estimated date. This method is designed for a standard menstrual cycle - 28 days.

Therefore, if the menstrual cycle is longer, then the date of birth will be later, since ovulation, with a long menstrual cycle, occurs later. When the menstrual cycle is irregular, the day calculated using this formula will not be correct.

Date of delivery by gynecological examination

Carrying out a gynecological examination of a woman, the doctor "by touch" can determine the most accurate day of birth, starting from 3-4 weeks, and up to 12. But at a later date, it is almost impossible to determine the approximate exact date and calculate the day. The reason for this is the different development of each fetus (the same as with ultrasound examination).

The first thing a gynecologist pays attention to during examination is the shape and size of the uterus. During pregnancy, the uterus changes shape, becomes spherical, and its size increases. Before its onset in healthy women, the uterus has a pear-shaped shape. Experienced gynecologists, based on the size of the uterus, set the most accurate gestational age and the approximate calendar date of the onset of labor.

The doctor can determine the birth number of a child by feeling the belly of a pregnant woman for a period of 14-16 weeks. The height of the uterus is determined by touch, and the height of the pregnancy is determined by its height and the date of birth of the baby is calculated. Also, this long-awaited day can be determined by measuring the circumference of the abdomen. But the data obtained in this way will not be accurate, since the waist circumference of each woman is different.

Is it possible to determine the date of birth at later stages of pregnancy

In some cases, it is difficult to determine the day on which the child will be born by the number of conception. For such cases, there is a proven method for determining the day of birth by the date when the baby moved for the first time. The baby begins to make the first movements in the womb at about 12 weeks. But since the child is still very small, the expectant mother does not notice them.

If a woman gives birth for the first time, then she will feel the movements of the fetus at 20 weeks of pregnancy. If the child is not the first, then the movements are noticeable as early as 18 weeks. Based on this, the date of birth is calculated in this way: during the first pregnancy, 20 weeks are added to the first day of the baby's movement, and 22 weeks during the second. Thus, you can get an almost exact number of the baby's birth. Some women may feel fetal movements early, at 14 or 16 weeks.

Gynecologists do not take such statements seriously, referring to the fact that these are ordinary bowel contractions. When determining the day of birth from such early sensations of fetal movement, the date obtained will not be correct.

Why is it impossible to determine the exact date of birth

It is impossible to determine the exact date of birth of a child even by the day of conception. A very small number of women give birth at the exact time set by the gynecologist. Despite the fact that pregnancy should last 280 days, childbirth can occur at 38 weeks, which will not be a pathology at all. Almost always, they occur earlier than the period established by the gynecologist, if the pregnancy is multiple.

The onset of the day the baby is born can be influenced by the course of pregnancy with the presence of such factors as high blood pressure in a pregnant woman, polyhydramnios, and some diseases.

To determine the day of birth, there is an online pregnancy calendar. You can determine the approximate date of birth using the online calendar by the day of conception. You must enter the date of your ovulation in the box, and the calendar will automatically determine the estimated day of delivery. The calendar will also allow you to calculate and control the approximate timing of fetal development.

Do not forget that the calendar is interactive, and a regular visit to the gynecologist is a must.

SUPPLIED
DATE OF DELIVERY

FIRST DAY
LAST PERIOD

Last day of menstruation: Estimated due date: Left before delivery: Zodiac:

The gestational circle is a convenient and simple tool for determining the gestational age, the expected date of delivery, as well as some other information about pregnancy. Our gestational disc allows you to determine not only the gestational age, date of birth, but also the height and weight of the fetus, and even the zodiac sign of the future child.

Using our gestational circle is very simple.

If you don't know how old you are, scroll the inner circle so that the green arrow points to the first day of your last period.

green arrow

Wherein arrow "today" will indicate today's date and week of pregnancy, as well as the height and weight of the fetus. Then arrow PDR indicate the expected date of birth.

arrow "today"

If you already know your deadline, then scroll the inner circle so that arrow "today" indicated the week of your pregnancy. Then it will also indicate the height and weight of the fetus, and arrow PDR will indicate the expected date of delivery. In this case, the green arrow will point to the first day of the last menstruation.

arrow PDR

What does "gestational" mean?

Many hear this word for the first time in a antenatal clinic. The Latin gestatio literally translates as "bearing." Therefore, "gestational" means "pertaining to pregnancy."

Gestational age is calculated from the moment of conception. Determining exactly when this happened is extremely difficult. It may take up to several days for a fertilized egg to implant after intercourse. At the initial stage of embryo development, even a few hours play an important role. Therefore, the inaccuracy in the definition of the "starting point" leads to a relative conditionality of the calculation.

Gestational disc for determining due date

There are different calculators, the main purpose of which is to establish the date of the baby's appearance. Gestational circle- an indispensable tool for preparing for childbirth and better control of the pregnancy process. With its help, every woman can determine the "X date" at home. This is necessary, since premature and late births pose the same danger. Therefore, it is important to calculate the expected day of delivery and, as it approaches, carefully monitor the signals of the body.

Statistics say that about 2% of babies are born on exactly the calculated day. The date that the calculator will show is better considered conditional. Most likely, the baby will be born a few days earlier or later. Normal childbirth is considered between 38 and 40 weeks. But each organism has its own unique features. Some women live up to 42 weeks, in which case maximum attention from doctors is required.

The gestational circle is one of the most informative calculators. In addition to the estimated date of birth, it can be used to determine the height and weight of the embryo as it develops. In addition, many parents are interested in what sign of the zodiac and in the year of which animal Eastern calendar a child will be born. For some couples, it helps to choose a name.

How is the gestational cycle

With this visual calculator, it is easy to determine the due date and track the height and weight of the fetus during pregnancy. The outer disk is divided into 12 months. Each day corresponds to one division on the scale. For convenience, long marks are indicated every 5 days.

The numbers 1-40 on the moving part of the disc correspond to the weeks of pregnancy. Also, using a background with different saturation, trimesters are highlighted: the first - from to , the second - from to , the third - from to . Closer to the center is the scale of weight, and at the last level - the growth of the fetus.

There are 3 arrows on the circle: green thin (first day of the last menstruation), EDD (estimated date of birth) and a static “today”. In the center of the circle, basic information is displayed: the beginning of the last menstruation, the expected date of birth and the baby's zodiac sign. In the area under the disk, the number of weeks and days before childbirth is instantly calculated, as well as zodiac characteristics.

How to use a gestational disc to determine the gestational age

The gestational circle is used by many obstetrician-gynecologists in different countries, including in Russia. The simplicity of the method allows it to be used by absolutely every woman.

When planning a pregnancy, it is especially important to keep a menstrual calendar. This will help to determine the expected date of birth as accurately as possible. To calculate the gestational age according to the gestational circle, it is enough to move the thin green arrow to the date of the start of the last menstruation. The PDR arrow will indicate the date of delivery, provided that the pregnancy ends at 40 weeks. Using the “today” arrow, it is easy to track the average height and weight of the fetus for each week.

For example, the last menstruation was from 12 to 16 December. For the calculation of the gestational circle, only the first date is important - December 12. Set the thin green arrow to this number. Twisting the arrow, pay attention to the center of the circle. This is much more convenient than peering into divisions. The “today” arrow indicates that the woman is at the beginning of the 8th week of pregnancy, the fetus has grown to 18 mm and weighs 1 g. You need to prepare for childbirth within 1-2 weeks from September 18th.

What should a woman do if she does not know the date of her last menstrual period?

To independently determine the date of birth of a child in this case, the gestational circle will be ineffective. Usually, doctors prescribe a blood test for hCG. Chorionic gonadotropin is a hormone that is released in the body of a woman after implantation of the embryo in the uterus for 4 obstetric week. From this point on, you can get the most reliable results.

When using the strip test at home, the second strip may be translucent. This indicates either the unsuitability of the test, or a small amount of the hCG hormone in the body. To obtain reliable results, you need to try again in a week if menstruation does not begin. A weakly pronounced second strip can appear in women taking hormonal drugs, regardless of pregnancy.

A home test only shows the presence of pregnancy. According to the result of a biochemical blood test, its duration is determined. Don't put off checking. Analysis for hCG is most reliable in the first 12 weeks. Gradually, the level of the hormone decreases, and at a later date it is difficult to determine the time of conception.

When the week of pregnancy is known, the gestational circle can be used to calculate the date of delivery and determine the size of the fetus. To do this, just set the “today” arrow to the mark corresponding to the current date.

For example, it's week 9. At this stage of development, the embryo has reached 23 mm and weighs 2 g. The expected date of birth is September 9. The green arrow indicates the approximate date of the last menstrual period.

Errors

Bearing a fetus is a complex process that each woman proceeds in a special way. Moreover, the course of the first pregnancy does not mean that the next ones will follow the same scenario.

The pregnancy calculator allows a certain error. In addition, when setting the initial data, errors are not ruled out. The calculation accuracy depends on individual characteristics organism. The pregnancy wheel shows the most accurate result with a standard menstrual cycle of 28 days. If the duration is longer, for example, 35 days, then ovulation will occur on average on the 21st day. This leads to an increase in the difference between obstetric and embryonic terms.

In addition, the error can be provoked by inaccuracy in determining the embryonic period. The spermatozoon is able to remain in the female body for up to 3 days. Fertilization can occur at any time. Taking into account all factors, including the individual characteristics of the body future mother, the error in calculating the estimated date of birth often reaches 2 weeks. Ultrasound gives more accurate results, although the method of calculating the beginning of the last menstruation is recognized worldwide as one of the best.

Why in the first two weeks the height and weight on the disk correspond to zero

You can see that in the first two weeks the indicators are zero. However, this period is part of the entire pregnancy cycle. The fetus in the womb develops surprisingly quickly. Therefore, in determining the date of birth, every day is important. At the same time, there are different terms - obstetric and embryonic, which are important not to be confused.

Some mistakenly believe that the first week is counted from the moment of conception. In fact, pregnancy begins on the last day of the menstrual cycle. Directly during this period, the birth of a new life could not occur. The moment of conception depends on ovulation and varies within a couple of weeks.

With a standard menstrual cycle of 28 days, ovulation occurs on the 14th day. In this case, the embryonic period will lag behind the obstetric period by about 2 weeks. In practice, this means that at the end of the first month of pregnancy, the actual age of the embryo is only 2 weeks.

Why sometimes calculations by different methods do not match

Many women are surprised to find that the dates of birth according to various calculations do not match. Which one to believe?

In official medicine, it is believed that embryos develop in the same way during the first trimester. On ultrasound, the gestational age is determined according to the table of correspondence between the size of the fetus and a certain period of development. For example, the calculation for the last menstruation shows the result of 12 weeks, and the diagnostician calls 11 weeks. More reliable is considered to be the period set during the first ultrasound. In this example, the difference is due to early ovulation, but it can be late. For the doctor, the result of an ultrasound examination is a priority.

During the second and third trimesters, each fetus develops at its own pace. Therefore, the data from the averaged tables may not fully correspond to reality. Deviations within one week are considered normal. In the ultrasound protocol, the specialist indicates what period the development of the fetus corresponds to.

The gestational circle gives an idea of how the unborn child develops every day. At the beginning of the first trimester, the embryo gains only a couple of grams every week, but the difference, for example, between and 21 weeks is an average of 71 g. It is interesting for every woman to know how the fetus changes. With the gestational circle, observation becomes simple and even more fun.

The most important weeks of pregnancy

In order for the fetus to develop correctly and the child was born healthy, the fact of pregnancy must be established as early as possible. It is not at all necessary that the expectant mother will intuitively feel the conception, or from the first weeks there will be obvious signs in the form of a heightened sense of smell, morning sickness, etc. It is not uncommon for a woman to find out about pregnancy only by her enlarged belly.

For pregnant women, the following factors are of particular danger:

Unhealthy habits.
Stress.
Unbalanced diet, deficiency of nutrients (mainly iron and folic acid).
Great physical activity.
Overheating or hypothermia.
Taking medications that are incompatible with pregnancy.
Infectious and inflammatory diseases.

It is necessary to prepare the body for pregnancy in advance in order to minimize the risks for the fetus and the expectant mother. But even if everything goes according to plan, there are times when extra care must be taken. If at any stage of pregnancy a woman feels severe discomfort, burning, or even unreasonable anxiety, you should visit a doctor.

When to be extra careful

Critical periods coincide with the phases of active growth of the embryo and placenta. The most dangerous weeks are the following:

I trimester - 2-3, 4-7, 8-12.
II trimester - 18-22.
III trimester - 28-32.

The insidiousness of the first weeks is that a woman may not be aware of pregnancy. As a result, they do not mandatory conditions. From 4 weeks, the main organs are formed. During this period, it is especially important to follow the doctor's instructions in order to prevent pathologies. At the last critical stage of the first trimester, the placenta is formed - a natural shield that will increase with the fetus.

The period from to 22 weeks is considered the most important. At this time, the unborn baby is most active. The biggest risks to the life of the fetus and the health of the woman are sexually transmitted infections. One of the main conditions is to use barrier protection during sexual intercourse.

By the beginning of the third trimester, the fetus is as similar as possible to a baby, but it is not yet able to survive separately from the mother's body. Causes of preterm labor may include placental abruption, infections, and isthmic-cervical insufficiency. To prevent this, you need to follow absolutely all the doctor's instructions, take care of your own health and eliminate stress.

There are no critical periods on the gestational cycle. This is due to the fact that they do not have to be difficult at all. The more you focus on the dangers, the stronger the destructive effect of stress. You can use the pregnancy wheel during the entire period of gestation. On the diagram, it is convenient to track the transition to a new trimester, the stages passed and the approaching date of birth.

Description

The universal pregnancy calculator is a convenient and practical tool for calculating a number of parameters that are important and interesting for a future mother. The calculator is a circle, similar to a watch dial, the inside of which can be rotated, setting one or another hand in the desired position. For example, by setting a thin green arrow so that it points to the first day of the last menstruation, you will determine the date of future births by the arrow "PDR", and by the arrow "today" you will find out what week of pregnancy you are now, and what is the height and weight of the fetus on present day. The Pregnancy Wheel can also be used in other ways. For example, if the birth has already taken place, then you can set the arrow "Ed" (estimated date of birth) so that it points to the day of birth. Then a thin green arrow will show you the date on which you had your last period before pregnancy. Among other things, the calculator determines the zodiac sign of the unborn child, and even his zodiac animal according to the eastern calendar.

The length of pregnancy from conception to birth is about 266 days, or 38 weeks. Since the date of conception is usually not known exactly, in modern obstetrics it is customary to calculate the gestational age from the first day of the last menstruation. With this calculation, it is approximately 280 days, or 40 weeks, since ovulation (the release of a mature egg from the ovaries) and, accordingly, fertilization usually occur about two weeks after the onset of menstruation. Turning to an obstetrician-gynecologist, many expectant mothers begin to worry about the difference in the date of birth - the one that the doctor calculated and the alleged woman herself. In order not to worry in vain, you need to know that there are two stages of pregnancy - obstetric and embryonic.

Embryonic term- this is the true gestational age from conception, it usually lags behind obstetric by about 2 weeks.

obstetric term doctors determine from the first day of the last menstruation before pregnancy. It should be remembered that all doctors use it: the size of the fetus, the timing of examinations, access to maternity leave and the date of birth is calculated taking into account only obstetric period pregnancy. It is also very important to know the exact gestational age for screening for the presence of genetic abnormalities in the fetus (ultrasound and blood tests), since these examinations are carried out at strictly defined periods of pregnancy.

During the first visits to the antenatal clinic, the obstetrician-gynecologist usually determines the expected date of birth (ED). For this, several methods are used.

Method 1. Method for determining the date of birth by the date of the last menstruation

This is the most common way to calculate the PDR. To calculate your due date, subtract three months from your last menstrual period. You need to add 7 days to the resulting date - this number is the same estimated date of birth. Obstetrician-gynecologists, when calculating the PDR by this method, usually use special obstetric calendars, which greatly simplify the calculations.

However, it is far from always possible to accurately calculate the PDR only with the help of this method. This happens in cases where a woman has irregular menstruation, or in those patients who have a regular but long menstrual cycle. For example, if a woman has a typical cycle length of 35 days (and not 26-28, like most), then, most likely, she will only be able to conceive on about the 21st day of the cycle (and not on the 14th, as in a 28-day cycle). Accordingly, the EDD calculated by menstruation will be a week earlier than the actual expected date of birth.

Method 2. about the date of ovulation or the date of conception

If the date of conception is reliably known, then you can calculate the estimated date of birth yourself by adding 266 days - this is the average gestation period. But even here there are nuances. You need to understand that even if a woman knows exactly the date of ovulation or the date of sexual intercourse, after which pregnancy occurred, this does not mean that she absolutely knows the date of conception. A spermatozoon that has entered the female body is capable of fertilization for an average of 4–5 days, sometimes even for a week, and a mature egg retains the ability to conceive for 2 days after ovulation. Therefore, even knowing exactly the date of sexual intercourse or ovulation, it is impossible to say with certainty that fertilization occurred on that day. It could have happened later. Therefore, the period calculated by ovulation or the date of conception cannot be considered absolutely accurate.

Method 3. Method for determining the date of birthon the first appearance at the antenatal clinic

Usually, the date of the upcoming birth and the gestational age are calculated by the doctor when registering for pregnancy. Doctors call this method of calculation - according to the "first appearance in the antenatal clinic." The gestational age, and, accordingly, the date of birth in this case is determined by the following parameters - the size of the uterus and the level of chorionic gonadotropin in the blood. Examining a woman in a gynecological chair, an obstetrician-gynecologist with both hands determines the size of the uterus. Most accurately, this method "works" in the early stages of pregnancy, up to about 12 weeks. The earliest period that can be determined by the size of the uterus is 5 weeks of pregnancy. By this time, the uterus is slightly enlarged, softened and becomes rounded. At later dates, the size of the uterus may vary slightly depending on the size of the fetus, the number amniotic fluid, The Structure Of A Woman's Pelvis.

To determine the gestational age and calculate the approximate date of delivery in the early stages, a blood test for hCG (human chorionic gonadotropin) helps. It begins to be produced in the body of the expectant mother with the onset of pregnancy, and gradually, until about the 11th week of pregnancy, its amount increases and then decreases slightly. Definition hCG concentrations in the blood at the beginning of pregnancy helps to accurately know its period. Having received the results of a blood test for hCG, it is worth paying attention that in the laboratory tables, which determine the correspondence of the hormone level to the gestational age, the embryonic period is often indicated. That is, to determine the usual obstetric gestational age, 2 weeks should be added to the result obtained.

Method 4. Method for determining the date of birth about ultrasound

When performing ultrasound in early pregnancy, measuring the size of the fetal egg and embryo, the gestational age can be determined with great accuracy. At 4–5 weeks, a small “black circle” is determined in the uterus during ultrasound examination - this is fertilized egg, in which the embryo will appear a little later. At about 6-7 weeks, the embryo appears in the form of a small "stripe", and you can see its heartbeat. More accurate is the period calculated by measuring the KTP of the embryo (KTP is the coccygeal-parietal size, that is, the maximum distance from the fetal head to its tailbone). After 12 weeks, the gestational age is determined by ultrasound by measuring the various sizes of the head and abdomen of the fetus, the length of its arms, legs, etc.

Until 9-10 weeks of pregnancy, the embryo grows proportionally, and its size in all women with the same gestational age will be approximately identical. In the future, these indicators will differ for expectant mothers of different nationalities, with different weight bodies, the weight of mom and dad at birth will also matter, and so on. That is, in more late dates During pregnancy, normally developing children of the same “age” can have different sizes (fluctuations can be about 2 weeks and sometimes even more), and in such a situation, it is impossible to reliably determine the gestational age according to ultrasound data.

Method 5. Method for determining the date of birthabout the first fetal movement

We note right away that this method of determining the PDR has recently been used less and less. It is based on the fact that women who are carrying their first child begin to feel his first movements on average at about 20 weeks of pregnancy, and pregnant women for the second or more times, a little earlier, at 18 weeks. That is why obstetrician-gynecologists recommend that the expectant mother remember the date of the first fetal movement and enter this data into the exchange card. To calculate the expected date of birth for women preparing to become a mother for the first time, 20 weeks must be added to the date of the first fetal movement, and for those expecting a second baby - 22 weeks.

However, this method of determining the date of the upcoming birth is often erroneous. What is the matter here? The problem is that the time when a woman can feel the first movements of the fetus is very individual and depends on her sensitivity, physique, as well as employment and experience. So, some expectant mothers feel the first movements already at 15–16 weeks, and someone only after 20. Slender women, as a rule, begin to feel them earlier than full ones. Expectant mothers who lead an active lifestyle, work hard, usually feel the movements of the fetus later than those who are less busy and have more opportunity to listen to their inner feelings. Pregnant women for the second or more times already know exactly how the baby's movements are felt, therefore, as a rule, they recognize the movements of the crumbs earlier than "inexperienced" primiparous women, who often mistake fetal movements for increased intestinal motility and gases.

All of the above methods allow you to calculate the estimated date of birth. However, it must be remembered that, of course, it is not absolutely accurate. It is not uncommon for a pregnancy to endure or be premature. provoke the onset of premature labor activity deviations in the development of the fetus, pathological processes in the body of the expectant mother, stressful situations, hereditary factors and many other reasons. Therefore, it is very important to realize that the calculation of the date of birth is a very conditional concept, regardless of the method used, and it is not possible to predict exactly when the baby will be born.

How is the estimated date of delivery for IVF calculated?

In case of IVF ( in vitro fertilization) the fertilization of an egg by a spermatozoon is carried out "in vitro" by an embryologist. Embryos develop in the laboratory for 3-5 days, after which they are transferred to the uterus. Doctors calculate the true duration of pregnancy after IVF from the date of ovarian puncture, that is, a procedure when a special needle is used to take the follicular fluid and the follicles contained in it for subsequent fertilization “in vitro”, and to determine the “usual” obstetric period, 2 weeks are added to the date of ovarian puncture.

If the transfer of the embryo to the uterus was preceded by its cryopreservation (that is, freezing in liquid nitrogen), to determine the exact gestational age, doctors add 5 days to the transfer date (this is the number of days the embryo develops before freezing), and to determine the obstetric period, add 2 to the received true period weeks, and calculate the date of birth.

This day requires special preparation. There are so many things to buy, cook, study a huge amount of literature, think through everything. possible options development of events. And it seems to us, women, that it would be a shame not to take into account something.

The whole pregnancy is not only a spiritual mood, but also quite material chores that should be carefully planned.

In a simple formula due date calculation the main component is the gestational age. Conception occurs most often on the days of ovulation, but not every woman knows when these very days come.

Everything is simple - exactly in the middle of the menstrual cycle, i.e. 12-16 days after the first day of the last menstruation.

For example, your last menstruation began on April 1, which means that the egg will go on its difficult path on April 12-16.

This due date calculation is suitable for women with an average menstrual cycle of 24-28 days. With deviations by day in one direction or another, the ovulation period also changes.

Let's assume that conception occurred in the middle of the last menstrual cycle. From this period of time, the long 40 weeks of your pregnancy begin.

Trying to calculate the due date by week

Some women mistakenly add 9 months and get a "supposed" secret date. This is not true, because pregnancy lasts a little longer - approximately 280 days or 40 weeks.

True, the doctor quickly eliminates this error and helps the patient decide with the help of a special calendar that any gynecologist has.

This calendar has the easiest counting system - from the first day of the last menstruation you need to subtract 3 months (April 1 minus 3 months = January 1), then you need to add 7 days to the resulting date (1 + 7 = 8), the result is the estimated date childbirth, which your gynecologist will enter on the card.

The second calculation method is to add 280 days to the first day of the menstrual cycle.

But you can’t rely only on these calculation systems, because for some, a full-term pregnancy can last 38 weeks, while for others - 42, all this is within the normal range.

Multiple pregnancy, as a rule, ends earlier than the date calculated by the doctor.

How to correctly calculate the term of childbirth by movements. Folk omens

To determine the due date, you can use folk omen, which for many centuries, even before the development of medicine, helped expectant mothers.

Exactly in the middle of pregnancy, primiparous women for the first time feel the movements of their baby - this significant event occurs, as a rule, at the 20th week.

Multiparous mothers identify tremors as early as 18 weeks. the walls of the uterus after childbirth become thinner, and therefore more sensitive, therefore, the second / third / fourth time intrauterine movements are perceived better.

By the time of the onset of intrauterine movements, you need to add 20 and 22 weeks for the first and subsequent pregnancies, respectively.

But this method is not very accurate either, because girls with different builds feel jolts on different weeks, a thin woman feels movements inside herself already at 15-16 weeks, and a denser woman at 21-22 weeks.

It is worth adding that not all expectant mothers can immediately correctly evaluate incomprehensible movements inside themselves - some confuse this action with an intestinal disorder, sorry, or a movement of the abdominal muscles (a weak cramp).

You can also determine the approaching birth already in the last trimester - by lowering the tummy. This process makes pregnant women feel a little better and takes place 2-4 weeks before delivery.

Calculate due date by ultrasound

Another method for assessing the term of childbirth is computer diagnostics, or more simply, ultrasound. In the early stages (up to 12 weeks), ultrasound can accurately determine the day of conception, based on the size of the head and torso of the embryo.

Up to a certain point (approximately 3-4 months of pregnancy), all babies develop in the same way, after which the genetic predisposition, the mother's diet and lifestyle affect.

Ultrasound examination in the second and third trimesters will have an error of up to 2-3 weeks, because the children are different and the weight of newborns can vary from 3 to 5 kilograms.

Inexperienced gynecologists can use the date calculated by the computer as a basis, and after the "estimated 40 weeks", begin to take unnecessary measures in connection with the "delayed" pregnancy.

Finally, almost as accurate as an ultrasound can be considered a gynecological examination on a chair.

An experienced doctor, by the size and shape of the uterus, will be able to determine the gestational age by touch, based on which further calculations will be made, which we determined at the beginning of the article.

It should be borne in mind that you cannot rely one hundred percent on any of the listed methods, they are approximate and give a result that can vary by 2 weeks in one direction or another. It is worth focusing on your feelings and nature, which is never wrong.

The question of how to determine the date of birth often causes discussion and controversy among pregnant women. The difference between your own calculations, the terms that are set during an ultrasound examination and those that the doctor writes on your card is completely confusing. Especially, in order to at least a little, but still make life easier for pregnant women, we have developed a program that independently calculates the estimated date of birth. Now you don’t have to visit a doctor or bother yourself with mathematical calculations, just to calculate the date of birth of your baby, you just need to enter the number in the right column of the calculator when your last menstruation began.

Negele's formula is a two-step puzzle.

The program that allows you to calculate the date of birth is based on the Negele formula, named after the German obstetrician who first proposed using this simple calculation method. It is known that pregnancy lasts an average of 40 weeks from the beginning of the last menstruation or 38 from the moment of conception. Negele simplified the calculations by reducing them to a few simple arithmetic operations - remember the date of the onset of menstruation that preceded pregnancy and subtract 3 months. You need to add 7 days to the resulting figure - this number is the same date of birth.

The question often arises - why should the calculation of the date of birth be based on the date of the last menstruation? This tradition, generally accepted in obstetrics, is justified, because not all women know exactly the day of ovulation, while most keep a calendar of menstruation. Bewilderment is also natural - after all, in the first, so-called "weeks of pregnancy", conception has not even occurred yet. Yes, this is true, and this period refers to the gestational age conditionally, for the convenience of obstetrician-gynecologists, according to the standards. The fetus begins to exist when it is already behind about 14 days of pregnancy. If the date of fertilization is reliably known, you can calculate the date of birth yourself by adding 266 days or entrust it to our calculator.

Deviation from the estimated date - is this the norm?

It is worth noting that the estimated date of birth for you is nothing more than a guideline. In fact, about 17% of women give birth on day X, the remaining 83% a little earlier or later. Predicting the onset of labor is beyond the power of any specialist. Moreover, normal, urgent births, that is, births that occurred at physiological times, are those that happened from 38 to 42 weeks of pregnancy. Often there is an unpredictable post-maturity or prematurity of pregnancy. Premature labor can be provoked by deviations in the development of the fetus, pathological processes in the mother's body, stressful situations, hereditary factors, and many other reasons. Therefore, it is very important to understand that the calculation of the date of birth is a very conditional concept, regardless of the method used.

However, there is some pattern, given which we can assume the development of the situation with a healthy pregnancy - the longer the monthly cycle, the longer the pregnancy lasts. Before you determine the date of birth, taking into account your individual characteristics, remember the duration of your menstrual cycle - from the first day of one period to the first day of others. If the cycle is longer than the standard 28 days, the pregnancy will probably last more than 40 weeks, and vice versa. Keep in mind that we are talking about the transfer of the estimated date of birth by no more than 5 days.

The calculator will help you calculate your due date from your period as accurately as possible, but you should remember that the data obtained from a medical examination is crucial, as it is more reliable. The reason for this approach is that menstruation is easily confused with bleeding that opened after conception and spontaneously stopped. Also, when examined in the third trimester or ultrasound of the uterus, the doctor can observe the degree of maturity of the placenta, the position of the fetal head in relation to the entrance to the small pelvis, the opening of the cervix, signs of full-term fetus and many other important data. By all these parameters, one can judge the readiness of the fetus and uterus for childbirth and the likelihood of their early onset. In addition, focusing on the size and proportions of the fetus during ultrasound, the doctor sets the age of the fetus in accordance with.