due date for the current week. How to determine the date of birth by the last menstruation. Methods and data for accurate calculation
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 they want to prepare for an important event, but they only shrug, because they are not able to accurately determine 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: 18.03.2019
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 the size of the uterus, 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), in each woman, an increase in the size of the uterus occurs with different intensity, depending on the individual characteristics of the 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 an increased sexual desire. In addition, her secretions (cervical fluid) become more sticky and thick, basal body temperature rises by a few tenths of a degree, the cervix rises, and the mammary glands thicken and become painful.
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 calculation using ultrasonic waves can also be attributed to the most effective methods that allow you to determine the term of delivery with an accuracy of 1-3 days. The most correct calculations will be if ultrasound is done during the period of 11-14 weeks of pregnancy.
- 4. To declassify the secret of the date of birth of your child will help his first stirring, which usually occurs on the 20th week (in nulliparous) and on the 18th - in the second and subsequent pregnancies. In ancient times, when there was no ultrasound, this method of calculating the due date was almost the only one.
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 determine the date of pregnancy with high accuracy, and hence the expected date of birth. The fact is that only with the help of ultrasound diagnostics, the doctor can observe the condition of the placenta, the position of the baby's head in relation to the entrance to the small pelvis, the level of opening of the 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 qualified he may be, is able to predict with high accuracy the date of the 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, for certain reasons, labor can begin 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 than the due date, then most likely the same thing 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, the 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.In medicine, there is a term applied to the timing of pregnancy - the expected date of birth (PDR). When expectant mothers come for the first pregnancy examination to the antenatal clinic and are registered, the doctor makes calculations and tells the woman the approximate day of delivery.
It focuses on the date of the last menstruation, which every woman needs to know. The gynecologist will definitely ask the patient if they started and how long they lasted.
If the expectant mother's menstrual cycle is regular (once every 28 days), the doctor adds 14 days to the start of menstruation and gets the approximate date of conception. The maturation and release of the female egg, that is, ovulation, occurs precisely at this time.
Women need to mark the exact dates of the onset of menstruation on a desktop or small calendar all the time, this can be useful both during pregnancy and any visit to a gynecologist for advice.
Spermatozoa can fertilize an egg immediately on the day of ovulation, or maybe after 1-3 days. Therefore, the exact date of conception today can only be said by a doctor doing an ultrasound scan.
If the pregnancy lasts no more than 12 weeks, the doctor can quite accurately name the date of conception. At a later date, this is more difficult to do. Therefore, it is important for the expectant mother to undergo an ultrasound scan in the first weeks of pregnancy.
After an ultrasound examination, the doctor will add 28 weeks or 266 days to the figure in the colleague's report, plus another 14 days that have passed from the last date of the start of menstruation to ovulation, and receive a check figure. She is reported to the pregnant woman as the date of the long-awaited event.
The birth of a baby is always a joy, but this joy appears under different circumstances. A child may be born before the term named by the doctor, or it may linger in the mother's stomach for various reasons.
The fetus is not born by women who have suffered severe infections or who suffer from endocrine diseases.
A full-term pregnancy is considered between 38 and 42 weeks. If a woman walks for more than 42 weeks, then this is a post-term pregnancy. The timing can be influenced by the health of the mother, her nutrition and environment, as well as the characteristics of the intrauterine development of the child.
To calculate the date of birth, the well-known Negele formula is also used. According to her, to the last date of the beginning of menstruation, you need to add 9 months and then add another 7 days.
By the day of the first movement of the fetus, you can also approximately calculate the date of birth of the child. You need to add 20 weeks to it if the pregnancy is the first and 18 weeks if the second. The error will be about 2 weeks, which is quite a lot compared to the date given after the ultrasound, for example.
So the expectant mother can calculate the date of birth on her own, but it will still be expected, as obstetricians and gynecologists say. Doctors advise not to worry more about the exact day when the baby will be born, but about how to successfully bear the child.
A healthy, optimistic mother will give birth well a day earlier and a few days later. The main thing is to have time to prepare for the desired event on time, and even the approximate date of birth will help this.
All parents-to-be are concerned about date the birth of a baby. Some people plan ahead. There are several ways to calculate the day of the baby's appearance. In the antenatal clinic, the obstetrician makes several calculations (according to the day of the last menstruation, according to the results of ultrasound, according to the first movement of the fetus and according to date). You can find out for yourself the estimated . But it is important to remember that all calculations are approximate and you will not be able to find out the exact birthday.
You will need
- - menstrual cycle calendar
Instruction
If you are planning a baby for a specific time (for example, in mid-January), then the date by date method can help you date conception. This process is laborious and difficult, but nothing is impossible. You can find out approximately the birthday, but you should remember that this date is indicative. For correct van counts, it is necessary to keep a diary of menstrual cycles for at least six. It is important to note the first day of menstruation and how many days it lasts.
Then count each menstrual cycle (from the first day of the previous menstruation to the first day of the next). So we get six digits for the last six months (you can also take the value for the year). Sum up all the cycles and divide the resulting figure by six. Get an average cycle. You are interested in calculating the time of ovulation, this is the first day on which fertilization is possible. The egg leaves their follicle and enters the fallopian tube (this is where the connection of the spermatozoon and must occur). Ovulation occurs in the middle of the cycle, so divide the resulting figure by another 2.
Since the cycles differ slightly in days, ovulation also varies, so add two days in both directions by the middle of the cycle. These are good days for conception baby. It is worth remembering that spermatozoa can live in the tubes from two to seven days, so the first attempt should be made a couple of days before the expected date of ovulation. The birthday itself is simple, you need to apply the Negele formula, for this, subtract three from the first day of the last menstruation and add seven days. You can also do it a little differently: add to date the first day of the last menstruation is nine months and seven days.
Sources:
- How to determine the date of birth by the date of conception in 2018
- how to find out the date of birth of a child in 2018
For some women, the birth of a child is almost the most important event in life. In order to prepare for this accomplishment in advance, it is necessary to know the expected birth, which can be determined by several methods, including the first movement of the fetus.
Knowing the exact due date is important for every pregnant woman, because it is better to go to the hospital in advance, on your own, and not in the ambulance. Today we will figure out why all children are born at different times and how to determine your gestational age.
The timing of childbirth depends on various reasons: is there a norm?
Gynecologists say that there is no standard term for normal childbirth - there are conditional limits. Normal delivery can be at 37 and 44 weeks. It is common for twins to be born at 36-37 weeks, and women with a long monthly cycle have every chance of giving birth after 42 weeks.
You need to understand that if a child was born normally developed at any time, this is the norm. With deviations in development and health due to the timing of childbirth, children are divided into premature and post-term.
- Babies with low weight, height, poor development of organs and bodies are called premature. Their mothers carried less than 37 weeks - up to 260 days of pregnancy, so the children could not reach the desired parameters. According to statistics, 20% of children are born prematurely.
- Postterm children are born after 42-44 weeks - in the period of 294-308 days of pregnancy. Do not think that when you overwear you will have a giant. On the contrary, there are signs of a post-term baby: thinness, dry, wrinkled skin, weak muscles. The reason for this condition is the aging and death of the placenta, through which nutrients were supplied. Approximately 10% of mothers walk.
From the foregoing, it follows that it is better to give birth at a period of 37-42 weeks. Knowing exactly when this moment should come, it is easy to navigate in case of premature contractions or overwearing.
Will doctors help if the due date is shifted?
Of course yes! Noticing the signs of impending preterm labor, you can contact the gynecologist and he will take action. With the threat of premature birth, bed rest and various drugs are prescribed that relieve contractions and relax the uterus.
When overwearing, at 40 obstetric weeks of pregnancy, the expectant mother is placed in the maternity hospital for observation. Examinations and stimulation with a drug that causes contractions speed up the process. If necessary, the doctor can open the fetal bladder, after which either childbirth begins or a cesarean is performed. After the water breaks, the baby will appear no later than 12 hours later.
If the term of childbirth has nevertheless shifted - do not despair, now they are nursing both significantly premature babies and “slightly” post-term ones. The most dangerous condition is a significant prematurity of the fetus - a baby can be born dead or with serious pathologies - every second postterm child has signs of suffocation, hemolytic jaundice, damage to brain regions caused by oxygen starvation, etc.
How to calculate the term of childbirth in gynecology
The obstetric term of pregnancy starts from the first day of your last period. It sounds a little strange, since at this time there is no child yet, but it is more convenient for doctors. In addition, the timing of pregnancy begins from the day of conception, which is usually considered the day of ovulation. Normally, ovulation occurs two weeks after the first day of the last menstrual period.
This is where the calculation problems start. there may be two in a month, it may move in the opposite direction. and ovulation specifically can occur due to classical stress, taking certain medications, inflammation in the reproductive organs, and other reasons. In some women, conception is delayed and can happen right on the “safe” day - just before the menstruation. In others, menstruation, on the contrary, can go after the onset of pregnancy. In these cases, it will be more difficult to determine the timing.
Primarily, the gynecologist sets the term based on the patient's interview and the data of the gynecological examination. By probing the uterus, the doctor determines its size, which corresponds to the period of pregnancy. The card records the estimated gestational age, for example 6-7 weeks, this indicator serves as a starting point for calculating the date of birth.
Formula for calculating the due date
You can calculate the preliminary date of birth (duration is abbreviated as PDR) using a simple formula. It is also used by obstetricians.
To calculate pregnancy, the date of the first day of the last menstruation is taken as the basis. Childbirth should take place after 40 obstetric weeks, which is. 280 days.
Formula for calculating the day of birth: Subtract 3 months from the first day of your last period, add 7 days to the result.
Example: The last menstruation began on September 5, we count back 3 months, we get June 5. Adding 7 days, we get the DA on June 12.
Online due date calculator: you can find out when to give birth right now
- Estimated date of conception.
- Timing of important stages in the development of pregnancy.
- Current gestational age.
- Term (date) of childbirth.
- Newborn zodiac sign.
It should be understood that this method cannot guarantee an accurate result, because an online calculator is just a set of formulas designed for a standard situation. Therefore, it is possible to find out the due date in this way only approximately.
How to determine the term of childbirth accurately - ultrasound of the fetus and no amateur performance!
The most reliable method for determining the timing of childbirth is an ultrasound examination of the fetus, called pregnancy screening. The sonographer, based on the readings of the device, compares the size of the fetus with the standard and makes a verdict - the gestational age and the date of the PDR (preliminary date of birth). Rather, this way you can very accurately determine the gestational age, and the date of birth will be estimated, since, as we noted above, it depends on many factors.
It is not in vain that among pregnant women there is a proverb “the PDR was invented by enemies”, since the coincidence of childbirth with the number set by the specialist does not always happen.
Causes of premature and delayed birth:
- Body parameters of a pregnant woman. The state of health, structure and condition of the uterus.
- Hormonal balance(labor activity begins under the influence of a hormone that stimulates uterine contractions).
- Fetal parameters. Development depends on the quality of the blood supply, genetic characteristics, location, etc.
- The presence of dangerous infections. A number of infectious diseases can cause premature birth.
- Injuries, stress and other factors.
Symptoms of violation of the timing of childbirth
It is quite simple to understand that something is wrong, the following symptoms correspond to childbirth outside the term:
- Premature labor begins with whining of the abdomen, the appearance of secretions, increased activity of the fetus. The stomach may not hurt - there will be a slight "sipping" in the back. Water may break - a large amount of liquid will flow out. All these signs are 3 reasons to call an ambulance.
- With true overbearing, the stomach and weight decrease. Milk may appear in the breast instead of colostrum. And on an ultrasound, doctors will determine whether the child is suffering from malnutrition or if you just have a prolonged pregnancy.
If you have had a premature birth, there is no need to panic. If the child breathes on his own and his weight is more than 2.5 kg, then everything is in order. A little love, care and mother's milk, and he will grow up to be a great person. There are many such examples in history. For example, Napoleon Bonaparte was born two months prematurely.
But if you have collected all the packages for childbirth at the 37th week, and already 42, then urgently go to the hospital. You should not hope for a doctor’s mistake - if the deadline was set on the ultrasound of the fetus, then he needs to be trusted.
Where to determine the date of birth in St. Petersburg?
A specialized one works in St. Petersburg. There is a new ultrasound machine with Doppler, which also allows 4D formats. Reception is conducted by leading specialists obstetrician-gynecologists with the highest qualification category. Prices for fetal screening are minimal, from 2-thousand rubles. - only 1000 rubles. Here you can also take tests for hCG and TORCH-complex.
When does a woman begin to be interested in the date of birth?
Then, when it comes time to prepare a dowry for the baby or when it comes time to go on maternity leave, to transfer all cases to colleagues for a while, and maybe much earlier, when only the expectant mother wants to influence the fate of her baby by planning his birth under a certain zodiac sign ?
One way or another, everyone is interested in determining the possible date of birth. In anticipation of changes in the composition of the family, you need to plan the time of holidays, the family budget, you may have to turn to future grandmothers for help.
From a medical point of view, the date of delivery is important when planning a caesarean section or for those women who will be calmer and more comfortable waiting for the moment of delivery in a hospital.
The abbreviation PDD means "estimated (planned) date of birth." It is worth paying attention to the fact that the date is precisely “estimated”.
No one can say for sure when your baby will decide to be born. But there are calculation formulas based on statistical data and the characteristics of female physiological cycles.
Many factors can affect the due date. Among them are the diseases of a woman, and the influence of ecology, and possible variations in the location of the placenta.
Important is the emotional state of the expectant mother and her age. But in the case of a normal pregnancy in a healthy young woman, the discrepancy between the actual date of birth and the calculated due date will be small (3-5 days).
Determination of the EDD by the date of the last menstruation
The Naegele formula, by which this calculation is made, is based on the fact that a normal pregnancy lasts 10 lunar months (280 days). Therefore, if a woman kept a monthly calendar and knew exactly their date, you need to count back 3 months, and then add another 7 days to the result:
EDD \u003d Date of menstruation - 3 months + 7 days
that is, if menstruation was on February 10, then counting back 3 months we get November 10, and adding 7 days we find out the PDR - November 17.
Calculation of EDD by ovulation
If you were planning a pregnancy and the date of conception, then you probably followed. allows you to determine. Adding 38 weeks (268 days) to this day, we get the possible date of birth.
ODD = Date of ovulation + 38 weeks.
How to calculate the estimated due date from the date of conception
If a woman knows exactly the date of sexual intercourse, which resulted in conception, another way to determine the date of birth can be offered. Physiologically, it is based on the same cycle as the basal temperature calculation, but does not require any preliminary measurements and charts.
EDD = date of conception + 266 days
That is, if sexual intercourse occurred on March 10, the expected date of birth will be November 22. The error of this formula is 3-5 days, it is associated with the period of life of a spermatozoon in a woman's body.
Determination of PDR during a medical examination is the most accurate method
If a woman registers for pregnancy in the early stages, then the condition and size of the uterus, the doctor will determine the duration of pregnancy and the approximate date of its completion (based on the "average" period of 40 weeks).
For a short period, the uterus is not yet palpable through the outer abdominal wall and a manual obstetric examination can tell about the period. But its characteristics are very subjective and depend on the qualifications of the doctor.
At 4 weeks, the uterus is the size of a chicken egg, by 8 weeks it will be larger - like a goose egg, and by 12 weeks it will reach the edge of the pubic bone.
An experienced obstetrician-gynecologist can determine the gestational age from these data.
Note that this technique works most accurately at the beginning of the first trimester. If a woman is not in a hurry for the first medical appointment, then there may be an error related to whether a large fetus is expected to appear, whether there is polyhydramnios, etc.
Planning the date of birth based on the results of ultrasound
During an ultrasound examination, it is possible to accurately determine the size of the fetus and its maturity. This will allow you to guess the date of birth.
Moreover, if you go for an examination in the first trimester and the gestational age is determined by the size of the fetal egg, then when you repeat, the doctor can tell you other data. This is not due to a mistake, just the intrauterine development of the baby is uneven.
The closer the due date, the more accurately you can determine the readiness of the child for birth.
For example, to plan hospitalization, preparation for a caesarean section.
Determination of the PDR by the date of the first movement
This method is less accurate than the previous ones, but is also physiologically justified.
All other formulas: calculation by the date of menstruation, ovulation or movement, are based on a standard 28-day cycle.
If a woman's menstrual cycle is less or more than 28 days, her physiological and metabolic processes may not fit into the calculated time frame. Moreover, there is not always a direct relationship here (that is, a woman who has a cycle of 25 days should not subtract 250 days from the date of the last menstruation instead of 280.
In any case, the calculation is carried out according to the standard formula. Just keep in mind that in your case, the likelihood of a baby being born a little earlier than the expected date increases).
The method with the greatest error - calculating the EDD by the date of the first movement - is further complicated by the fact that not every woman can accurately determine the moment of the first movement. The movements of the child are often mistaken for peristalsis or gases.
In addition to the objective calculation error, the date of birth can be affected by:
- chronic diseases of a woman;
- bad habits;
- heredity;
- or multiple pregnancy;
- mother's age;
- a cold or bacterial infection already during pregnancy;
- repeated births;
- fetal pathology;
- stress.
As soon as she finds out about the pregnancy, the woman is already interested in the expected date of birth. After all, by this moment you need to prepare a dowry for a newborn, if necessary, provide yourself with assistants or pick up a nanny for older children, plan a family budget, taking into account replenishment of the family and a long vacation for the mother.
Someone is in a hurry by the time the baby is born to improve living conditions, make repairs or move closer to relatives. And all these issues need to be resolved by a specific date, the DA.
The methods for calculating the date of birth were very relevant, the calculation formulas were developed by obstetricians in different countries. With the advent of ultrasound, other methods with a large error began to be used less frequently. But they still arouse the interest of those who want to make a calculation without consulting a doctor, or at the stage of pregnancy planning.
How to find out the date of birth? About the method of calculating the date of birth
For estimated due date calculation obstetrician-gynecologists have a very convenient and simple formula: 9 months and 7 days are added to the date of the first day of the last menstruation. And you can calculate even easier - from the first day of the last menstruation, count back 3 months and add 7 to the resulting number.
Estimated date of delivery = date of the first day of the last menstruation + 9 months + 7 days.
Estimated date of delivery = date of the first day of the last menstruation - 3 months + 7 days.
But these terms are typical for the average woman with an average 28-day menstrual cycle and ovulation on the 14-15th day of the cycle.
The average pregnancy lasts 266 days (38 weeks) from conception, or 280 days (40 weeks) from the first day of your last period. If the menstrual cycle of the future mother is shorter or longer than the average 28 days, or ovulation did not occur on the 14-15th day of the cycle, then the pregnancy can also be longer or shorter. Therefore, it is generally accepted that 280 days is an approximate number of days of pregnancy and a child can be born between the 266th and 294th day (38–42nd week) of pregnancy.
Calculation of the date of birth by the day of conception is not an accurate method for determining the due date. Even if you know exactly the day when sexual intercourse took place, this does not mean that conception occurred on that day, since spermatozoa are able to remain active in the vagina for up to several days.
How else can you determine the gestational age and calculate the date of birth?
Determining the gestational age with ultrasound
In the early stages, up to 12 weeks of pregnancy, it is possible to calculate the date of birth using ultrasound quite accurately. Over long periods, this is often difficult due to the fact that each child grows at his own pace. Namely, such indicators as the sizes of different parts of the fetal body are the basis for calculating the gestational age.
Determination of the gestational age during a gynecological examination
During pregnancy, the uterus begins to gradually increase in size and takes on a spherical shape. With a gynecological examination up to 12 weeks, the doctor can determine the approximate gestational age by the size of the uterus. For periods of more than 16 weeks, when the uterus extends beyond the womb, you can determine the period by the height of the standing of the bottom of the uterus during examination of the abdomen. Naturally, this method of determining the gestational age is not accurate.
Determination of the gestational age by the first movement of the child
Another auxiliary method for determining the gestational age and calculating the date of birth is by stirring. Despite the fact that the child begins to make movements quite early, the mother can only feel them when the baby reaches a certain weight. This usually happens in nulliparous women at 18-20 weeks of gestation, and in multiparous women 2 weeks earlier. However, some women claim that they feel movements as early as the 14th week and sometimes earlier.
Using all of the above methods, you can more or less accurately determine the gestational age, but the date of birth will still be approximate. This means that the chance of giving birth on the due date +/- 3 days is about 70%. Do not forget that the child's readiness for extrauterine life also affects the date of birth. Some children of the so-called morpho-functional maturity can reach the 38th week, while others - at the 41st.