Find out by monthly pregnancy. Accurate weekly pregnancy calculator

04.08.2019

A woman, having learned from a doctor about her desired pregnancy, will definitely want to find out the “age” of the future crumbs. There are several ways to determine the date of birth of the baby, both independent and with the help of specialists. How to correctly calculate the gestational age, as well as how the real term differs from the obstetric one, we will try to tell in this article.

The obstetric term, which is set by gynecologists at the first appointment with the expectant mother, differs markedly from the real one, but is the most accurate parameter. It is believed that pregnancy occurs at the moment of direct conception or fertilization of the mother's egg. This usually happens around the middle of the menstrual cycle, so if a woman knows the day when the egg leaves the follicle and ovulation begins, then she can accurately calculate the gestational age.

Basal body temperature (BT)

To do this, you need to daily, remaining in a horizontal position in bed, measure the temperature by the rectal method. After menstruation, in the period of 10-14 days, it most often does not exceed 37 degrees, and during and after ovulation, it can rise to 37.2-37.3 degrees. The day of conception does not always coincide with the time of sexual intercourse. The sperm cell has the ability to survive from three to seven days in anticipation of the appearance of the egg from the ovary. And the lifespan of the mother cell itself is limited to 24 hours. Therefore, if sexual intercourse occurred 5-7 days earlier than ovulation occurred, then conception can occur 5-7 days later than coitus. Therefore, experts argue that this method of counting for determining the embryonic period is not entirely accurate. In addition, each woman, due to her individual characteristics: a certain menstrual cycle, the day of ovulation and the possibility of re-emerging the egg from the ovaries, will have her own developmental period of the fetus, which cannot be determined one hundred percent.

In obstetric practice, the date of the first day of the last menstruation is used. The error of this method is only 7-14 days. The obstetric period is calculated in two ways: 10 average menstrual cycles (28x10) or 280 days are added to the first day of the last menstruation; in the second case, 3 months are subtracted from the same date and 7 days are added (Negele's formula). In the ideal case, when the exact date of ovulation is known (days 12-16 of the menstrual cycle), 264 days can be added.

Note! At the appointment with the gynecologist, the expectant mother will find out the obstetric period, since doctors do not take into account the rest of the calculations.

Ultrasound procedure

For many years, the ultrasound method has been quite actively used in the diagnosis of fetal development. The most accurate gestational age is obtained using studies conducted at the earliest stage of pregnancy - up to 8 weeks. The development of healthy embryos these days is identical and it is possible to determine the gestational age up to a day by the size of the fetus. In the future, the children begin to show their individuality, any healthy fetus may have minor deviations (for example, growth is slightly below normal or the size of the head is slightly larger). If this difference fits within a period of no more than 7-10 days, then doctors usually do not take this circumstance into account, but if it is a period of two or more weeks, then doctors diagnose intrauterine growth retardation and recommend paying attention to proper balanced nutrition , walks, a healthy lifestyle that will help normalize the development of the embryo.

A gynecologist's consultation on the first day of pregnancy delay is usually not needed, since the doctor will not yet be able to determine whether the uterus is enlarged as a result of PMS or conception. The perceptible growth of this female organ in connection with pregnancy begins only at the end of the first trimester. In the second or third week of delayed menstruation (for a period of 5-6 weeks), the uterus reaches the size of a chicken egg, at 8 weeks - a goose, at 10 - usually acquires the size of a female fist.

HCG and gestational age

How to correctly calculate the gestational age using human chorionic gonadotropin? Ideally, a blood test from a vein is not used to determine the timing of an “interesting situation”, but for the early diagnosis of possible complications. In the second week, an approximate table of hCG values in the blood of a pregnant woman contains a parameter from 25 to 150 IU per ml, and in the eighth - up to 70 thousand IU per ml. Serious deviations from the table values indicate a serious pathology, such as missed or ectopic pregnancy.

First fetal movement

Doctors say that in first-time pregnant women, the feeling of the inner presence of the baby occurs exactly at 20 weeks of pregnancy, in re-pregnant women - at 18 weeks. This date is an important step in the correct calculation of the gestational age. It is easy to notice the movement, especially when lying on your back.

Uterine length

Starting from the second trimester of pregnancy, gynecologists measure the length of the uterus with a centimeter tape in the patient lying on the couch. In a future mother, the uterus adds about a centimeter in size every week. In addition, there are special tables that can be found in manuals on gynecology and obstetrics.

Heart tones

The embryo's heart begins to beat already at four and a half weeks (or 2-3 weeks after a woman's period is missed). This is noticeable in early ultrasound examinations. Through an obstetric stethoscope, the fetal heartbeat is heard much later, approximately after the date of the beginning of the movement of the future crumbs. Poor hearing can be caused by a placenta located closer to the anterior wall of the uterus or significant abdominal deposits of adipose tissue.

No matter how hard you try to correctly calculate the gestational age to the day, most likely it is unlikely to succeed. This can only be done hypothetically. Your baby will be born into the world only according to the laws of Mother Nature, when he is ready for this. Good luck in this difficult and noble cause!

Video

You can learn more about calculating the gestational age from the following video:

(duration 28 days), or 280 days. In fact, these terms fit into 9 calendar months, plus seven days. Therefore, it is customary to talk about 9 months. The birth of a baby at 38-42 is considered normal if there are none indicating immaturity or overmaturity. If the child was born later than this period, then it is considered post-term, otherwise - premature.

Obstetrician-gynecologists start counting the gestational age from the first day of the last menstruation. Usually, the actual period is 13-16 days less, since conception occurs approximately in the middle of the menstrual cycle, i.e. at the time of ovulation. However, to avoid confusion, doctors start counting the gestational age 2 weeks ahead of the date.

If you do not know the exact date of conception, then it is most correct to count the weeks of pregnancy based on the results of an ultrasound scan. Scheduled research is carried out at 12-13. As a rule, it coincides with the deadline set at the first appointment. But, if there are discrepancies, then it is better to focus on the period set with the help of ultrasound.

In some cases, there may be a discrepancy between the size of the fetus and the gestational age. For example, as a result of polyhydramnios, the presence of tumors, etc. These data are taken into account by specialists in the study. In this case, they put the number of weeks of pregnancy, obtained from the calculation from the first day of the last menstruation, and with the help of ultrasound at later times, they correct it.

Start with

Cycle duration 21 days. 22 days 23 days 24 days 25 days 26 days 27 days 28 days 29 days 30 days 31 days 32 days 33 days 34 days 35 days 36 days 37 days 38 days 39 days 40 days

Defining it is not as easy as it might seem. Most moms-to-be don't realize they're pregnant until the first missed period, by which time the pregnancy can be up to five weeks. This means that it is not enough to simply count nine months from the date of the pregnancy test, even if you try and take into account the weeks that have passed since the last ovulation.

It will be possible to determine the exact date of birth of your unborn child only if you remember exactly the day of the ovulatory cycle at the time of fertilization.

HOW TO USE THE CALCULATOR TO DETERMINE THE DATE OF BIRTH OF A CHILD

You may not know that menstruation and ovulation are considered the first two weeks of pregnancy. Therefore, it is not surprising that the calculations can be difficult, especially if your cycle is longer or shorter than the average (28 days).

Although pregnancy usually lasts 40 weeks, the date of delivery can depend on various factors. Our calculator takes into account your last period start date and cycle length to quickly calculate an estimated due date based on your cycle length.

If you know the exact date of conception, enter it. The calculator takes into account the first two weeks that fall on menstruation and ovulation.

1.First specify first day of your last period, as well as the average duration of your cycle. This is the number of days from the first day of one period to the last day before the start of the next period. If you know which one the day conception occurred, choose this option as an alternative.
2. Enter relevant dates into a calculator.
3. Then press To know!

Remember that the calculator calculates an approximate date, not an exact date. After all, every pregnancy is different.

WHAT TO DO WHEN YOU KNOW YOU ARE PREGNANT

Having calculated the date of birth, you will know the approximate date the baby will be born, and you can start preparing for this.

If you haven't already, start by making an appointment with your doctor, who will confirm your pregnancy with a blood test and physical examination, and help you determine a more accurate due date.

At each follow-up visit, the doctor will determine the size of your uterus and monitor your baby's development. The highlights of these examinations will be when you first hear the baby's heartbeat and also when you see it on the sonogram. As your pregnancy progresses, your due date may change.

Remember that throughout pregnancy, first of all, you should listen to the advice of a doctor. However, there are some things you can do yourself. Check out the rest of our website for more information.

The pregnancy calculator allows you to calculate the exact due 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 pregnancy week 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 scroll through the slider for the 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 the full list of 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 a summary of the fetal growth for that 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 calculation method 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 an average 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. All precise calculations and any other manipulations should be done only by your attending physician.

The online pregnancy calculator will help you calculate the gestational age, determine the expected date of birth, calculate the age of the fetus, and find out when the end of the first and second trimesters will come. The pregnancy calculator is a free service. Depending on the individuality of the organism, some data may not match.

Each pregnant woman keeps her own calendar, where she records all the changes that occur to her during pregnancy. However, the modern pace, a lot of family concerns do not always allow you to track on your own what week of pregnancy is going on and how the baby should develop. A pregnancy calendar comes to the aid of busy mothers: this is a complete description of all the changes that are happening at this stage with mom and baby. Thanks to this, a woman can easily track how much the baby weighs, what she should feel, what problems await her. But in order to find out how the child develops, you need to determine what the woman's gestational age is.

First day of last menstrual period:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 January February March April May June July August September October November December 2018 2019

Average cycle time (days):

22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

Calculation results

- Estimated date of conception

- Fetal age

- Gestational age

How to find out the time of conception?

Traditionally, in order to determine what the current gestational age is, a woman comes to the antenatal clinic in the clinic. The doctor conducts an examination, if necessary, prescribes an ultrasound and focuses on the last menstruation in the setting of the term. Based on this date, a calculation is being made when the mother should give birth.

But it is worth warning women that such a calculation will not always tell you the exact day of delivery. In medicine, there are two terms for determining pregnancy: obstetric and real. What is their difference?

The obstetric term helps to determine when the pregnancy began, based on the date of the last menstruation. In this case, the date of conception is not taken into account, since it is unknown to the doctor. The doctor proceeds from the concept of a woman's standard menstrual cycle, which lasts 28 days. Therefore, conception could occur during ovulation on the 14th day after the start of the cycle. It turns out the difference between the obstetric period and the embryonic period by 2 or even 3 weeks.

You can find out the real time more precisely if you undergo an ultrasound scan. However, ultrasound is prescribed no earlier than 10-12 obstetric weeks, and the woman's curiosity is much stronger.

How can you find out your own gestational age in order to subsequently focus on the calendar?

To do this, it is desirable to know the date of conception, or at least the possible days when this could happen. If you cannot set the date, you can use reusable pregnancy tests. The devices are equipped with sensors that determine the gestational age. The error of such devices is small.

You can calculate the gestational age on your own, based on the obstetric calculation method. But if this is difficult for you, an online calculator will come to the rescue. This is a program on the site that will calculate the approximate date of your ovulation and, therefore, the expected date of conception.

How does the calculator work, and what is needed for this? You just need to enter the first and last date of your period. The online calculator itself will calculate the middle of the term and determine the date of conception of your child.

If you know the date of conception, an online calculator will also help determine the time when pregnancy occurred. The way it works will be different. You need to enter the date of conception into the calculator, and it will calculate the gestational age by weeks. So you will know exactly which week goes on what dates you have, and you will be able to observe from the descriptions how your child grows.

When is the birth?

Now is the time to find out the due date. The same calculator that determined the date of conception will help you calculate the date of birth. The online calculation is based on the data on the date of conception or the last menstruation. In the latter case, you will know the due date based on the obstetric term.

If you know exactly how many weeks you have, then you can guess from when to expect the onset of labor. This usually happens at 38-40 weeks. Some women live up to 42 weeks: such a pregnancy is not considered post-term. It should also be noted that an error could occur when determining the gestational age. An online calculator can also make a mistake, as it calculates based on generally established observations. In addition, you could enter inaccurate data into it.

Practice shows that the date of birth is the date of the beginning of the last menstruation, to which 9 months are added. In these numbers, we should expect the completion of the family. But what to do if it is not possible to determine the period by menstruation, since the woman no longer remembers the exact date?

HCG analysis

If a woman does not follow the regularity of the cycle and does not remember the date of the last menstruation, the calendar is unlikely to help here. In this case, doctors recommend doing a blood test for hCG, a hormone that allows you to determine the presence of pregnancy even in the early stages.

HCG (chorionic gonadotropin) is produced in a woman only during pregnancy with a fetal egg. A biochemical blood test is able to determine its amount in the body and, on the basis of this, establish the presence and duration of pregnancy. The most informative are the first 12 weeks of pregnancy, when the level of hCG is still high. Gradually, it begins to decline, and a blood test will no longer give reliable data.

Approximately determine the size of the fetal egg, and according to it - what is the current gestational age, the doctor can also when examining the vagina and palpation.

Why do you need to know the exact date?

Not all women are attentive to their pregnancy and calculate the period by weeks. They think that it is the task of the doctor to calculate the gestational age in order to subsequently calculate the date of birth. During pregnancy, they do not think about how many weeks they have now, and how the baby should develop.

In vain, since no one better than the mother herself will determine whether the baby is comfortable inside. Dangers lie in wait for a pregnant woman at every turn, and it is better if she knows her due date by weeks. A calculator and a calendar can help with this, so it is not necessary to ask a doctor every time.

If you do not know how many weeks of pregnancy you have, open the calculator on the site, enter the required data, and you will receive an answer. It will help you remember the doctor's recommendations and warn yourself and your baby against possible complications. Isn't it nice to see in the photo and video how your baby is growing week by week? After all, you can only look inside with the help of ultrasound, but this happens only three times during the entire pregnancy.

The need to undergo screenings is another reason why a woman needs to know the exact gestational age. Studies, including a blood test for genetics and ultrasound, take place within strictly defined terms. If you do the analysis sooner or later, you can get an inaccurate answer.

Do not neglect the calculation of the gestational age by weeks. This will give the woman valuable material to determine if the baby is developing according to the norm, if there are any deviations, and what studies still need to be done.

What errors are possible?

Unfortunately, if the exact date of conception is not known, any weekly pregnancy calendar or conception calculator may not be accurate. The baby development calendar is based on the data that was originally determined. What if they are incorrect?

Unfortunately, errors cannot be avoided. According to statistics, in almost 20% of women during pregnancy, the difference between obstetric and embryonic terms is 14 days. If a woman's cycle is long, such as 35 days instead of 28 days, ovulation may only occur on day 21. Consequently, the difference between the obstetric term and the real one will be even greater. 1 week of the embryonic period will be equal to 5 or 6 obstetric weeks.

But even in the formulation of the embryonic period there is an error. It is several days, since the sperm can be stored in a woman's body for 3 days, so fertilization could not occur on the day of ovulation, but later.

Calculating the gestational age is a painstaking task. Not always a calculator and even a medical analysis can give an accurate answer. A woman should listen to her own feelings: they will help her find out by feeling what the gestational age is now, and how correctly the doctor determined it.

In order not to miss the fact of pregnancy and know exactly when fertilization happened, a woman should be attentive to the signals of her own body and conduct regular monitoring of her health. To do this, you need to keep a calendar where the dates of the beginning and end of menstruation, the facts of suspicious vaginal discharge (if any) will be recorded. This will allow you to establish the onset of the disease in time and avoid consequences for yourself and the child.

To be healthy and give birth to a healthy baby, a woman must be attentive to herself. The calculator on the site and the pregnancy calendar will help her with this!