Pregnancy age by last menstruation online calculator. Determination of pregnancy at home in the early stages. Method for determining the gestational age by the date of ovulation

10.05.2019

How to calculate due date

Stanford University adheres to the following calculation formula:

Set the first day of your last period.
Count back three calendar months
Add a year and seven days to this date.

For example, your first day of your last period was September 9, 2019. We count back three months and get June 9, 2019. We add a year and seven days, we get June 16, 2019 traffic rules - the expected date of birth.

The website team understands how important it is for expectant mothers to be on the alert, therefore it offers a new service - an interactive pregnancy calculator, designed specifically for you.

With the help of our calculator you will be able to accurately calculate the date of delivery and all the main points of your pregnancy. The calculation will take only a few seconds, the page will refresh and you will receive your weekly pregnancy calendar. Now you will know exactly when the baby will be able to move his fingers, respond to your touch, hear your voice.

If it seems to you that you became pregnant earlier or later than your menstruation, then after a planned ultrasound, you will be able to calculate the gestational age again, based on a number of medical indicators. Thanks to our service, you will know the answers to many questions regarding your gestational age and expected date of birth.

Benefits of using
pregnancy calculator:

Every woman with the onset of pregnancy has many questions. When will the belly start to grow? When will the baby start moving? When to register with antenatal clinic And when can I go on maternity leave? When can we expect the baby to be born? All these questions can be answered on our website. We have described for weeks all the changes in the body of the mother and child, indicated all significant events;

Using the pregnancy calculator, you can find out the exact dates of each trimester, significant dates(conception, childbirth, prenatal leave);

The doctor at the reception will definitely ask about changes in the woman's condition. With the help of a calculator it is very convenient to look at what to look for, at what time certain symptoms should appear;

An obstetrician-gynecologist will definitely draw up an examination plan, tell you which week you need to take certain tests, do an ultrasound scan and others. instrumental research. Electronic calendar pregnancy is a convenient reminder of when and why you need to go to the consultation. We have tried to explain why each analysis is performed and how to evaluate its results.

The online pregnancy calculator is a handy service that helps a woman to have a clear idea of the course of pregnancy and the sequence of events.

Approximate calculation for the average cycle duration and the onset of ovulation - plus 14 days to the beginning of the last menstruation.
Full 40 weeks.

Pregnancy is one of the most exciting and at the same time crucial periods in the life of every woman, and therefore it is not at all surprising that each of us wants to know the date of birth as soon as possible. However, this issue often causes numerous disagreements and disputes. Expectant mothers “torture” doctors with their questions, because you want to prepare for important event, however, they only shrug, because they are not able to determine with high accuracy the date of the birth of the long-awaited baby.
In order to Calculate the date of birth, click the "find the date of birth" button.

Today: 02.03.2019
Date of the first day of the last menstruation:
Conception most likely happened (+-2 days):

Estimated due date:
Left before birth:

The calculation of the expected date of delivery (ED) is carried out in several ways, each of which is indicative. That is, if, according to estimates, the baby should be born on January 1, then it is not a fact that this will happen with absolute accuracy on that day. Very often there are deviations from the expected date in one direction or another. And childbirth can begin either 2 weeks earlier or later. I bring to your attention a fairly simple, but very effective way to find out the probable due date of a child, which has been successfully used by many doctors in clinics for quite a long time.

Calculation on the last day of menstruation

So to be on your own calculate gestational age and on it to determine the expected day of birth, it is necessary to remember the date of the beginning of the last menstruation. It is on its basis that all calculations are made. From this date, you must subtract 3 months and add another 7 days to the result. The resulting number will be the estimated date of birth of your long-awaited baby.
For example, the date of the last menstruation is April 22. So, from this date you need to subtract 3 months. Subtract and receive - January 22. We add another 7 days to this figure and get January 29 - this day will be the expected date of birth.
It is worth noting that this method of calculation is best suited for women with a regular menstrual cycle that lasts 28 days.

4 Alternative Ways to Calculate Due Date

1. You can find out the due date, with a fairly high accuracy, by visiting the gynecologist's office. The doctor will not prescribe any tests for this, he will simply measure uterus size, which will increase in size in accordance with the age of the fetus. However, this method of calculating the date of birth of the baby is effective only in the first trimester of pregnancy. In the later lines (in the 2nd and 3rd trimester), for each woman, an increase in the size of the uterus occurs with different intensity, depending on individual characteristics organism.
2. You can calculate the date of birth by ovulation, which is the most favorable period in which conception is most likely to occur. On such days, a woman usually experiences increased sexual attraction. In addition, her secretions (cervical fluid) become more sticky and thick, basal body temperature the body rises by a few tenths of a degree, the cervix rises, and the mammary glands thicken and become painful.

So, in order to find out when your baby will be born, according to ovulation, you need to add 280 days to this day (pregnancy duration). The resulting term will be the date of birth. If the period in which ovulation occurred is unknown, then calculate the middle of the last menstrual cycle, and then add the rest to it.
In the same way, you can perform calculations on the date of conception. However, you should be aware that this period does not always coincide with the day on which sexual intercourse occurred. Fertilization of the egg, as a rule, occurs only on the third day.

3. Hardware computing using ultrasonic waves can also be attributed to the most effective methods, which allow you to determine the term of childbirth with an accuracy of 1-3 days. Most correct calculations will be if ultrasound is done during the period of 11-14 weeks of pregnancy.
4. Declassify the secret of your child's date of birth will help him first stir, which usually occurs at the 20th week (in nulliparous) and at the 18th - with the second and subsequent pregnancy. In ancient times, when there was no ultrasound, this method of calculating the due date was almost the only one.

Once future mom feels the first tangible tremors of her baby in her stomach, then from that moment 20 weeks should be counted. The resulting date will be the probable day of the birth of the child. If the birth is not the first, the movements are usually felt earlier - at the 18th week, so you will have to add not 20, but 22 weeks to this period.

The effectiveness of hardware methods in calculating the term of labor

A study of the fetus in the third trimester on an ultrasound machine allows you to accurately determine the date of pregnancy, and hence the estimated date of birth. The point is that only with ultrasound diagnostics the doctor can observe condition of the placenta, the position of the baby's head in relation to the entrance to the small pelvis, the level of opening cervix, signs of fetal maturity, as well as many other important factors. All these parameters are decisive in determining the readiness of the future baby and his mother for childbirth.

Deviation from the deadline - is it the norm?

As mentioned above, all calculations of the estimated date of birth are nothing more than an approximate guideline, which should not be heavily relied upon. According to statistics, only 17% of women give birth on the appointed day, while the remaining 83% - either earlier or later. Thus, we can conclude that no specialist, no matter how smart and skilled he may be, is able to predict with high accuracy the date of onset of labor activity.
Normally, childbirth can occur between 38 and 42 weeks. pregnancy. The birth of a child will not be premature or belated, but normal and physiological. Sometimes by certain reasons generic activity may start prematurely. This happens due to deviations in the development of the fetus, stressful situations, various pathological processes occurring in the mother's body, hereditary factors, etc.
Often there is a re-carrying of pregnancy due to the fact that in the first trimester there were any complications. In addition, maternal heredity should be taken into account. If your mother and grandmother gave birth much later due date, then, most likely, the same awaits you. Therefore, it is very important to realize that the calculation of the term of childbirth is a very complex, conditional and individual issue for each expectant mother.

How do the features of the menstrual cycle affect the date of birth?

The length of a woman's menstrual cycle also affects the duration of childbirth. For example, if it exceeds the standard twenty-eight days, then most likely the pregnancy will last more than forty weeks, and vice versa. However, in this case deviation in one direction or another usually does not exceed 5 days. It is worth noting that errors are often made in such calculations, since very often ordinary bleeding is taken for menstruation, which opened after the fertilization of the egg.

The pregnancy calculator allows you to calculate exact date and find out what week of pregnancy you are currently in, as well as the expected date of delivery. To calculate, select the date of the first day of your last period at the top of the calculator and click on the "Calculate" button. The calculator will then automatically display your current week pregnancy and expected due date.

For each week of pregnancy, two exact dates are displayed: the start day and the end day. The interval between them is exactly 7 days. You can scroll through the weeks of pregnancy using the arrows. The full list of weeks from 1st to 40th is at the very bottom of the calculator. By clicking on them, you can also flip the slider to desired week. The trimester of pregnancy to which each week belongs is indicated by Roman numerals at the bottom (near the slider) and in the upper right corner of the cells (in complete list weeks). Also, the trimesters are marked in pink, orange and blue, respectively. In general, the very concept of pregnancy trimesters is rather arbitrary and their boundaries are not clearly defined. We took as a basis the most common classification, in which the second trimester begins at the 14th week and ends at the 28th. Only your obstetrician-gynecologist can calculate trimesters more accurately after an ultrasound scan.

In the images you can see a rough illustration of the development of the baby inside the womb for each week. To the left of the images is short description fetal growth for a given week. For more complete and detailed information, you can find by clicking on the "More" link, which is located under each description.

Method for calculating the gestational age

The calculator calculates the so-called "obstetric" gestational age. It differs from the actual date by about two weeks. This method calculation is used in gynecology, because it is very difficult to calculate the exact day of conception. Therefore, the calculation is based on the first day of the last menstruation, the date of which, as a rule, every woman remembers. 280 days or 40 weeks are added to this day. Thus, the first two weeks of the obstetric period you are not yet pregnant, because. ovulation has not yet occurred (based on medium duration menstrual cycle of 28 days). This method is not completely accurate because some women ovulate late or early. But, in general, for most expectant mothers, such a calculation turns out to be quite accurate.

In any case, we draw your attention to the fact that the pregnancy calculator allows you to calculate the term using the most general formula, which does not take into account the individual characteristics of your body. It cannot be used for self diagnosis or any other medical purposes, since the results of its calculations are for informational purposes only. by all precise calculations and any other manipulations should only be handled by your doctor.

Every woman, having learned that she will soon become a mother, wants to understand when the first meeting with the baby will take place. To do this, you need to find out the gestational age, you can calculate it in several ways.

But even the most accurate calculations they will only give, because not every pregnancy lasts exactly 40 weeks. Approximate terms are set by the doctor when registering and within 9 months can be slightly adjusted.

Ways to determine the duration of pregnancy

You can calculate the gestational age different ways. Each has its pros and cons. Some calculations are easy to do at home on your own, armed with a calendar, other methods of determining the period require the help of a doctor and medical equipment.

By date of ovulation (conception)

This counting method is the most accurate, especially on early dates. Conception can only occur during a period that lasts several hours, and over the next day, while the egg remains in the fallopian tube. If the spermatozoa enter the uterus later, then fertilization is no longer possible.

There are three ways to determine the day on which ovulation occurred:

Calendar . Most often, menstruation begins exactly 2 weeks after ovulation. Knowing the duration, you can calculate the day when the egg left the ovary and was in fallopian tube- period of conception. For example, if 30 days pass from the beginning of one period to the beginning of others, then the calculation of ovulation will be as follows: 30-14 = 16 (conception occurred on the 16-17th day of the cycle). But this method turns out to be inappropriate in cases where ovulation or, that is, occurs not after 14 days, but after 10-13 or 15-18. Such a calculation will also fail to be performed by women with.
. The principle of operation of this test is based on the identification high level luteinizing hormone in urine or saliva. Its amount varies throughout the cycle and reaches a maximum on the eve of ovulation. When the test gives, it means that conception can occur in the next 24-48 hours. Pharmacies can be purchased, which react to the concentration of luteinizing hormone in saliva. They are designed for one or more applications. A more common option is strip strips that determine the level of LH in the urine.
Schedule . This method requires a long measurement of temperature in the rectum. The procedure should be done in the morning without getting out of bed. Record all data daily. Ovulation on the chart will be determined by a sharp increase in values by 0.4-0.6 degrees. In the first half of the cycle, it is not more than 37 ° C, on the day the egg is released from the ovary, it increases and stays at about the same level until the next menstruation. The disadvantage of this method is that similar changes may not be caused by ovulation, but, for example, by recent sexual intercourse or a cold that is starting.

Do not confuse the day of sexual intercourse and the day of conception. Fertilization of the egg possibly within 24-36 hours after ovulation. Spermatozoa, entering the body of a woman, can remain alive for up to 7 days. That is, within a week (usually 3-5 days) after intercourse, conception can occur.

By the date of the beginning of the menstrual cycle

This is how the obstetric gestational age is calculated. It does not take into account on which day the conception occurred and the development of the embryo began. Therefore, it is not entirely accurate, the error can be from 7 to 14 days.

How to calculate the gestational age by the last menstruation? First you need to remember when they started. For further calculations, it is better to prepare a calendar. It is necessary to determine the number of days from the first day of the last menstrual bleeding to today. This will be obstetric period pregnancy.

You can find out the expected time of birth of a child in the following ways:

From the beginning of the last menstruation, count 40 weeks.
From the beginning of the last menstruation, subtract (count back) 3 months, and then add 1 week. Move this calendar date forward one year.

For example, a woman's last period began on October 20, 2016. According to method 1, we add 40 weeks, we get the expected date of birth - July 27, 2017. We calculate in 2 ways: October 20 minus 3 months - July 20, plus 1 week - July 27. The dates match, both calculations are correct.

This method of calculation is most accurate for women with a 28-day menstrual cycle. How to make it easier - correctly calculate the gestational age will help online calculator, but again only for the reference cycle. In other cases, a doctor can confirm the date more reliably.

By date of first movement

The method of determining the date of birth by the first movement has been used for over 100 years. It was very relevant at a time when medical technology and knowledge were not developed. Now doctors do not use it, since in other ways it is possible to calculate the gestational age in weeks more accurately.

It is believed that the first stirring occurs exactly in the middle of pregnancy. Based on this, you can calculate the expected date of birth. Embryonic development fetus lasts 38 weeks. So, by the day when the woman felt the first tremors, you need to add 19 weeks - this will be the expected date of birth. And if we subtract the same period of time, we get the date of conception.

But the error of such a calculation is very large:

With the help of modern medical equipment, it has been established that the baby can begin to move as early as the 12th week of pregnancy, but women feel it later.
Most often, women who will give birth for the first time begin to feel the baby's movements at week 20, and those who already have children, early at 18. It turns out that the calculations for the date of birth will be as follows: we add 18 weeks to the day of the first movement (for those who have a first pregnancy) or 20 weeks (for repeated pregnancies).
All women have different sensitivities. According to the observations of doctors, lean women leading a sedentary lifestyle are the first to determine movements. They celebrate them as early as the 14th week of pregnancy.

Given that the pregnancy itself can take from 38 to 42 weeks, the error in this calculation becomes even greater. Doctors mark the day of the first movement on the chart, but it is not used to adjust the estimated date of birth.

According to measurements of the uterus

FROM certain period, namely from 6 months, the height of the fundus of the uterus in centimeters corresponds to the number of weeks of gestation. Therefore, by measuring this parameter, you can calculate the approximate date of birth and gestational age.

The standing height of the bottom of the uterus is the distance from its upper edge to the pubic joint. The gynecologist measures it from 14-16 weeks, before this period it is located behind the pubic bone, and you can find out its dimensions only during a vaginal examination.

Of the tools you need only a centimeter tape. You need to lie on your back, after emptying bladder. Release the stomach from clothing and carefully feel it along the lobar line: in the place where elastic belly the base becomes soft, the bottom of the uterus (its upper border) is located. You need to measure from this point to the pubic joint.

To make it easier to find the upper border of the uterus, you can focus on the standard indicators:

at 12 weeks it reaches top edge pubic bone, the dimensions of the entire uterus are comparable with the size of the head of a newborn child, it is still impossible to probe and measure it;
at week 16 - located 6 cm from the pubic joint, you need to feel the distance from the navel to the pubic bone;
20 - 12 cm above the womb, determined approximately 2 fingers below the navel;
at 24 - palpable at 22-24 cm from the pubis, just in the navel area;
28 - 27-29 cm, which is about 2-3 fingers above the navel;
at 32 - it is installed 31-33 cm from the womb, palpated between the navel and the beginning of the sternum approximately in the middle;
at 36 - 35-37 cm, determined at the level of the beginning of the sternum;
at 40 weeks, the baby is positioning the head in pelvic bones, and the uterus descends slightly, the height of its bottom is 32-33 cm, it is palpable between the navel and the beginning of the sternum.

How to calculate what the exact gestational age is now and when the birth will occur, knowing the height of the uterine fundus? This can be done when the indicator reaches 24 cm. From this period, the number of weeks of pregnancy is the same (24 or more). Considering that the entire pregnancy lasts 40 weeks, the calculations are easy to make.

The accuracy of this method is not high, so at present it is practically not used. But these measurements are still carried out, their goal is to identify possible complications. If the height of the fundus of the uterus does not correspond to the gestational age, this may be a sign, hydatidiform mole, tumors and other pathologies.

ultrasound

Ultrasound can be performed early. Already from 3-5 weeks, the fetal egg begins to be visualized, determining its location helps to exclude, and the diameter - to set the period.

At 5-6 weeks, the embryo itself is viewed, the doctor measures the coccyx-parietal size (). There are normative values for this indicator for certain periods. From the comparison, the gestational age and the approximate date of delivery are calculated.

In the 2nd and 3rd trimesters during ultrasound, the following indicators are measured:

biparietal size - the segment between the parietal tubercles;
Head circumference, chest and belly;
thigh bone length.

For all these values, there are also norms. By comparing the measurement values, the gestational age can be calculated and the date of delivery can be estimated. But as individual differences become more apparent every week, the probability of error is constantly growing. The size of the fetus reflects the disease of the mother, hereditary factors, especially the course of pregnancy. Therefore, by the end of gestation, a child can weigh 2700 grams or 4500 - both options will be the norm.

So, determining the duration of pregnancy and the date of birth using ultrasound will be accurate up to 12 weeks. The more time has passed since this period, the less reliable the results will be.

According to the level of hCG

Human chorionic gonadotropin is a hormone produced membranes from 6 days after conception. The first weeks are rapid increase its concentration in the blood: halved every 2 days. Then its production gradually decreases, and from 9-11 weeks the indicators begin to decrease.

You can find out the concentration of hCG in the blood by passing it for laboratory analysis. There are certain norms for the content of this hormone in plasma for a certain period of pregnancy. Each laboratory uses its own reagents, the sensitivity of which is different. Therefore, there is no single table of standard values.

Method for determining the gestational age by hCG level in the blood is practically not used, although it is quite accurate, especially in the early stages. The analysis is carried out to detect pathologies, for example, or implantation of the embryo outside the uterine cavity.

What difficulties may arise?

No matter how accurate the methods for calculating the duration of pregnancy, they all give only an approximate date of birth. It is impossible to say with a 100% guarantee when the baby will be born.

According to statistics, 17% of pregnant women give birth on the day expected by doctors, and the remaining majority - sooner or later. It turns out that even the most qualified specialists and high-tech equipment is not able to perform an absolutely accurate calculation.

Normal labor is considered to begin between 38 and 42 weeks of gestation. In these cases, the fetus is considered full-term. With some complications, labor begins. The cause may be the pathology of the development of the child, stressful situations, various disorders in the mother's body, hereditary factors. All this must be taken into account when calculating the gestational age.

The child is often observed when, in case of admission hormonal drugs, with violations of the functions of the ovaries. Influences and hereditary factor: if there were late delivery, it is likely that they will repeat.

Menstrual cycle and ovulation physiological processes. The cycle length ranges from 24 to 35 days. Therefore, any calculations based on them will always have a certain amount of error.

Standard calculations are based on the assumption that the pregnancy lasts 40 weeks, and this is only true for a 28-day cycle. The time of ovulation is also determined by static data: 14 days before the onset of menstruation. In fact, this process can happen 3-4 days earlier or later.

You can calculate the gestational age in different ways. The most accurate are the determination by the date of conception (ovulation), by last day monthly and according to ultrasound for up to 12 weeks. Other methods can be considered auxiliary, they allow a large share of the error and for this purpose are not used in medical practice.

Even the most exact way may be wrong for 1-2 weeks, or even more. This is due to the fact that the duration of bearing a child ranges from 38 to 42 weeks (normal), the menstrual cycle - from 24 to 35 days, the onset of ovulation can also occur a few days earlier or later than expected in standard calculations.

Useful video on how to calculate the gestational age and due date

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Use our EDD (Estimated Due Date) calculator to calculate indicative date the birth of a baby. The calculation can be made by the date of conception, or by the date of the last menstruation. Select the appropriate option and enter the original date. As a result of the calculation, you will receive the coveted date, as well as accurate calendar pregnancy with comprehensive information about the development of the fetus and medical indications for each week. Calculation results can be saved to email or printed.

EDD Calculator - Estimated Date of Delivery
with pregnancy calendar

Calculation option:

If you know the exact date conception of a child, use the first option. Or choose the second option, the estimated date of delivery will be calculated automatically, according to the date of the beginning of the last menstruation.

Start date of last menstrual period:

Cycle duration:

On average 28 days. If you don't know the exact length of your cycle, leave the default value.

28 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 days

Conception date:

Women tend to get as much information about their new condition as possible by learning about pregnancy. It is also important to find out how to calculate the date of birth and the sex of the child, whether it is worth using an online calculator for this, what features and algorithms it includes. All this and much more is discussed in our article.

Calculation of the due date - principles and algorithms

You can use several options to calculate the exact date of birth: an online calculator, your own calculations, the result of a doctor's examination. But whichever option is chosen, their principles and algorithms are very similar.

Determination of the term by the date of conception

The easiest way is to make a weekly pregnancy calendar and calculate the date of birth if the girl knows the date of fertilization. Usually, difficulties arise with this, because a couple who decides to have a baby tries not to miss any of auspicious days. Therefore, if it is not possible to calculate the due date by the date of conception, you can try to determine it yourself. To do this is not at all that difficult.

To do this, it is worth remembering how the process of childbirth proceeds in the body of a girl:

Bubbles form in the ovary immediately after menstruation. One is ahead of the others in growth and speed of development. It is in it that the female cell appears. The rest of the follicles gradually disappear.
The cell reaches its peak of development and is ready to function, breaks through the follicle and is released. Her path lies in the direction of the uterus. Here, in the genital tract, fertilization by sperm must occur under favorable conditions. This moment will need to be known in order to calculate the date of birth by the date of conception.
The fertilized cell continues the journey and completes it with implantation in the uterus. This happens only 7 days after meeting with the male cell.
Under the condition of normal fixation, the fetus begins its growth and development. This process is promoted by progesterone, which produces the corpus luteum. The latter acts as a temporary gland, which grows on the wound from the rupture of the bubble. It always appears, but if fertilization does not happen, it structurally collapses by the day of the next menstruation, leaving a small scar on the ovary.
There are changes in the structure of the mammary glands under the influence of progesterone. Signs of a new situation begin to appear, which is why the woman begins to look for ways to calculate the date of birth, draw up a calendar using a calculator, what tests to take and when to visit her doctor for the first time.

Ovulation and date of conception

So, in order to make a pregnancy calendar and calculate the date of birth, you need to calculate the day of fertilization of your cell. How to do this, subject to the presence of daily sexual intercourse, for example? At first, it is worth remembering that conception occurs only at the moment when the cell has already freed itself from the follicle shell and has passed into the sexual path. Those. it is very easy to calculate the due date by the date of ovulation. As you know, this process is very short and is usually equal to a day, which is why the error in the miscalculations is practically eliminated.

How to calculate due date from last period

If the girl does not know the exact day of ovulation, it can be calculated based on her cycle readings. You need to look at the calendar and calculate the date of birth according to the last menstruation.

Data for accurate calculation

The following parameters need to be assessed first:

Cycle duration. Calculate the number of days between the indicated dates of menstruation for the last few periods. The standard is 28 days, but there are also values in the range of 21-33 days.
Systematic. Compare the received numbers with each other. Normally, they should be equal, with a maximum deviation of 1 day. In such a situation, there will be no problems with how to accurately calculate the date of birth. There are also failures, when in one month there is suddenly a shift for 1-2 weeks. This is caused by stress, illness, the use of hormone-containing drugs, climate change, etc. You don't have to worry, it's normal. If the cyclicity is broken and every month the terms differ by 5 or more days from each other, the rhythm is recognized as irregular. This is not scary, just calculating the gestational age and the date of birth will be an order of magnitude more difficult. If such failures have not occurred before, it is better to consult a gynecologist on the reason for the detection possible problems.
Duration and characteristics of menstruation. Normally, they should be of the same type in structure, abundance and duration every month.

Ovulation in the menstrual cycle

Knowing the parameters that the calendar gave us, it is not difficult to calculate the date of birth if you identify the day of ovulation. It is calculated when you need to calculate the date of birth by menstruation, based on such knowledge regarding the duration of the flowing phases in the female cycle:

The time of follicle and cell generation is 11-17 days. It differs significantly in women due to the different content of hormones in the body and their balance. The standard is 14 days, but it is possible for girls whose cycle is unchanged long time and is equal to 28 days.
The release of the cell and its path to the uterus. If spermatozoa are not found along this path, it will last only a day. Rarely, vital activity can be higher - up to 2-3 days, usually, it dies after 12 hours. That is why pregnancy, to calculate the date of birth by which would remain the last unresolved issue for the girl, the date of ovulation must be identified as accurately as possible in order to assign a productive act.
Functioning corpus luteum in the absence of a fetus, it ends exactly after 14 days. This criterion is the same for everyone. Very rarely, it can be 12-13 days.

The last number, which is equal for all girls, is reliably known, and therefore ovulation is considered according to it. The formula looks like this: subtract 14 from the duration of the monthly process. The result obtained must be counted from the previous menstruation and marked on the calendar. This is the date of ovulation, which is the moment of conception, because. on other days it is not possible due to the lack of a finished cage. Now it is already easy even to prescribe a birth calendar and calculate it according to the date of conception, revealed in the described way.

Methods for determining cell yield

Tests. After using the strip according to the instructions (dipping it in urine for a few seconds or holding it under a stream), you need to look at the change in the color of the reagent. It shows the concentration of luteinizing hormone, which reaches a maximum when the follicle ruptures.
Microscopes. These are reusable devices that allow you to see the pattern of salts contained in saliva. It gradually changes, acquiring the features of a fern by the day the cell appears. It will be enough to calculate the day of birth by the date on which it manifested itself most clearly.
Allocations. It is known that during the development of the follicle, the vaginal mucus has a dense structure and does not come out. And by the time of the "birth" of the cell, it liquefies and is excreted in a very abundant amount. In structure and color, it is similar to egg white. observed until cell death.
Pain. Unpleasant sensations are felt in the direction of the ovary. By tearing the follicle, the cell creates an ordinary wound on it, which causes a little pain. Relying on your own feelings and remembering the exact date of the onset of pain, it will be easy to calculate the date of birth by conception.

Prediction of the gender of the child - what you need to know

We figured out how to correctly calculate the date of birth, first by identifying the exact day of fertilization. Now it remains only to count 40 weeks from the date, making notes on the calendar. Sometimes girls want to not only calculate the date of birth, but also find out the sex of the child early. This can be done by comparing the date of intercourse with ovulation:

The act fell on the date of ovulation or a day later - a son is expected. This is due to the characteristics of male spermatozoa with a Y-chromosome, which are much faster than X-type cells. Y will overtake a female cell many times faster, leaving no chance for slow brothers. Having identified pregnancy, it is very simple to calculate the date of birth and the sex of the child according to the principles described above.
The act happened in 1-2 days - the maximum probability of conceiving a daughter. This is explained by the fact that Y-cells die in a day, being in the genital tract, and therefore do not wait for the appearance of the female. X cells last up to 3 days, and therefore, although they are very slow, they will already be waiting for the female by the time she appears in the genital tract. When compiling a calendar to calculate the date of birth and the sex of the child in such a situation, one must also take into account the day the cell appeared, despite the fact that the act was earlier.

Thus, regardless of the fulfillment of the conditions for “receiving” a baby of the desired gender, it will be necessary to calculate the date of birth according to the day of conception. Indeed, without the presence of a female cell in the pathways, spermatozoa do not fertilize anyone.

Calculator - how to calculate the due date online

Calculation by date of conception or last menstruation

Therefore, today there are two options for filling in data:

calculate the date of birth by conception: the calculator counts the standard days of pregnancy from famous girl day;
calculate the date of birth by menstruation: the calculator determines the moment the cell appears, therefore the formula requires a cycle length parameter. If the girl does not know him, it is recommended to leave 28 days. But in this case, an error is possible.

Pregnancy calendar is a useful feature

As a result of the calculation, the girl receives a specific date of the expected birth. But that's not all. Our service has additional function, which allows you to calculate the date of delivery and pregnancy by week to calculate at the same time. At the same time, the girl receives a table painted for each week of pregnancy with an indication of her dates, containing such interesting and useful information:

Development of the fetus: at each stage, the embryo undergoes certain changes, because it is constantly developing. You can find out when his muscle tissue begins to grow, form internal organs and when he starts to hear.
Medical indications: the baby's body at each stage, based on the characteristics of formation, requires different microorganisms which are listed on the table. Also, the girl will know when to expect toxicosis, discomfort, heartburn, how to protect yourself from them without harm to the crumbs.

After the girl calculated the date of birth and by weeks, having received detailed plan actions, you can save it to yourself in in electronic format by clicking on the "send by mail" icon. It is also available to print the table to have it at hand.

Medical indications - tests, ultrasound, etc.

By using the pregnancy calculator to calculate the due date on our website, you also get data on the required dates for tests and ultrasounds. This will allow you to control the actions of the doctor and better prepare for visits and examinations. Calculate the date of birth online is a simple way, due to which the girl does not need to make miscalculations on her own, and in return she gets the maximum useful information for your particular case.

Irregular Cycle Calculation

Some difficulties await ladies with irregular processes, then there may be difficulties in detecting ovulation. They can only calculate the date of birth by the date of conception, the online calculator in this situation will give the correct answer. If they want to calculate the date of birth based on the last menstruation, the calculator may be wrong, because the result depends on the length of the cycle, which is always different for a girl.

Determination of the date of birth by a doctor

Many are sure that only a specialist observing the patient is able to calculate the exact date of birth. But it is worth remembering that it is based in its readings on the same data as the above methods. The doctor, in the event that he did not observe the girl before pregnancy, will ask her for the following data:

First day blood secretions;
Cycle duration;
systematic;
The presence of failures in the rhythms and deviations.

Based on these criteria, he will calculate and determine the expected date of delivery. Most likely, this date will coincide with the date of birth, which can be calculated from the date of conception online. There may be a small error of 1 day due to the "human" factor or unaccounted for moments.

Ultrasound calculation accuracy

If the doctor wants to calculate the date of birth by ultrasound, the calculator is more likely to lose. Indeed, in the study, he is able to see the size of the embryo and compare it with the standard. However, a mistake is also possible here, because each organism develops in its own way, and the embryos can differ somewhat in size in girls at the same time.

Determination and stimulation of ovulation

Because, calculate correct date childbirth is available only mathematically, based on knowledge of the day of fertilization or by finding out the exact date of ovulation. If a girl has problems with this, she should go to the hospital already at the planning stage so that the doctor can control the process of egg development on ultrasound. Already from the 5th day after menstruation, examinations begin with a frequency of once every two days. When the cell exit is approaching, ultrasound can be prescribed daily. Having found a burst follicle or a day before, the doctor will inform the patient about the most successful moment for fertilization.

From the video you will find out on which day you need to do an ultrasound to find out if the follicle is maturing

A similar scheme of examinations occurs if the girl has problems with cell reproduction (the follicle does not develop or burst). This is due to the insufficiency of the hormone estrogen, and therefore it is administered forcibly, through a special course of drugs.

With such strict observation of the stages of cell development, in order to accurately calculate the date of birth, a calculator is not required. After all, the girl and the doctor will reliably know the day of fertilization. At follow-up, the doctor will follow the moment of implantation gestational sac. A woman will not need to perform a test or donate blood, because the ultrasound will show the fact that the embryo is fixed, which guarantees pregnancy, and calculating the date of birth by the date of conception for a doctor, knowing all the facts, will not be a problem.

conclusions

The expected date of birth, which can be calculated in several ways, will give the girl an accurate idea of the duration of the wait for her little “miracle”. You can use any of the above methods or try all of them. Usually, the deviations between them are no more than 1-2 days. We recommend using our calculator and calculating the date of birth by menstruation (or by conception) online. In this case, in addition to the expected date of birth, in addition, future mommy will receive a kind of guide to action and tools to control the development of his baby by weeks.