Gestational age- one of the main components that a gynecologist needs to know about for proper management of pregnancy. After all, on the basis of this, the doctor will prescribe the necessary examinations, tests, routine ultrasounds, monitor intrauterine growth and development of the fetus, and identify possible violations during the pregnancy. In addition, determining the due date allows you to fairly accurately calculate the date of birth and the date of maternity leave. It is necessary for the woman herself to know the duration of her pregnancy in order to mentally prepare for childbirth, have time to prepare a room or corner for the unborn baby, and purchase all the necessary accessories and clothes for him.

In this article we will look at how to determine the duration of pregnancy.

Calculate by monthly

For a woman who comes to register at the antenatal clinic, the gynecologist first of all asks a question about when her last period began. It is from this date that he begins to keep a record, despite the fact that fertilization has not yet occurred. It is known that fertilization of the egg occurs on the day of ovulation, which occurs in the middle of the menstrual cycle. This method of determining the gestational age is called “obstetric”.

An online calculator will help determine the period:

How to determine the gestational age by the date of conception

It is known that conception occurs only during ovulation within 24 hours after the egg leaves the follicle. And the viability of sperm in the female genital tract is up to 3 days. It turns out that the date of sexual intercourse does not always coincide with the date of conception.

Ovulation occurs in the middle of the menstrual cycle. A woman who monitors her menstrual cycle can quite accurately calculate the onset of ovulation. In addition, many at this time develop characteristic symptoms: aching pain in the lower abdomen, breast swelling, irritability, copious vaginal discharge, increased libido.

It is worth noting that only those women who have a regular menstrual cycle can determine the gestational age by the date of conception.

Online calculator:

(calculation will take a few seconds)

How to calculate using ultrasound

It is possible to find out the gestational age using the results of an ultrasound examination (ultrasound). It is determined according to the size of the fetus. The first ultrasound of the expectant mother is performed at 12-14 weeks, but it is still impossible to determine the exact date, since the development of the fetus occurs individually in each woman. It is possible to find out the age of the fetus by ultrasound with an accuracy of one day only in the first weeks after conception.

Determination during examination by a gynecologist

A gynecologist can determine a woman's gestational age by the size of her uterus during a gynecological examination. At 5-6 weeks, the size of the uterus can be compared to a chicken egg, at 8 weeks - to a goose egg. Later, it will be more difficult to determine how many weeks a woman has based on the size of her uterus.

Find out the due date by the first fetal movement

In the first pregnancy, a woman begins to feel fetal movements at 20 weeks, in the second - at 18 weeks. But this method does not always allow one to determine the period, since some expectant mothers may feel the first movements of the fetus earlier or later than the indicated weeks - some, due to the structural features of the body, cannot feel the movements of the fetus, others confuse the work of the intestines (increased gas formation) with movements.

Determine by hCG

Human chorionic gonadotropin (hCG)- one of the most important indicators indicating the onset of pregnancy and its normal development. The hormone begins to be produced in the female body after implantation of the embryo into the wall of the uterus. The level of hCG in the blood allows you to find out the approximate age of the fetus. With multiple pregnancy, the level of the hormone in the blood increases in proportion to the number of fetuses.

The long-awaited pregnancy has arrived, and you really want to know when you will see your baby? To calculate the gestational age and the expected day of birth, it is enough to know just one date: the day of the start of the last menstruation. It is from this that the gynecologist will calculate the gestational age when you come to the clinic to register.

Calculate gestational age online

Only a few women can accurately name the date of conception of a child in order to accurately calculate the real gestational age. And even in this case, the birth of a new life may occur on another day, when the future parents do not know about it. At the same time, almost every woman remembers the date of her last period, which is why obstetricians take it as a starting point. Theoretically, ovulation—the period when an egg is released ready for fertilization—occurs in the middle of the menstrual cycle. Therefore, between the actual age of the fetus and the obstetric gestational age (which begins on the first day of the last menstruation) there is a difference of approximately two weeks.

So, to calculate your gestational age online, you need to remember when your last period started. Two weeks are added to this day: it is during this period that the egg fully matures and fertilization can occur. Next, you can calculate the expected date of birth in two ways: the first is when forty weeks are added to the date of the first day of the last menstruation. The second is that three months are subtracted from the day when conception could have occurred and seven days are added to it.

But if you don't like fiddling with calculations, the interactive pregnancy calculator will do it for you. Enter your data (the date of the first day of your last menstrual period) and within a second you will receive the result of your pregnancy in weeks and days.

Calculate gestational age by date of conception

This calculator can also be used to calculate the gestational age based on the day the child was conceived, if you are confident in the accuracy of this date. In this case, you will find out the actual (gestational) gestational age, which will correspond to the age of the fetus. The obstetric date that your doctor will give you on the first day of your last menstruation will differ from it by approximately two weeks (that is, it will be longer than the gestational age).

Using our calculator to calculate the gestational age by week, you can also find out the approximate due date and begin to prepare for it in advance: find a comfortable maternity hospital and a good doctor, study breathing techniques during childbirth, choose a comfortable position for childbirth, think about partner childbirth, arrange children's room and stock up on everything necessary to care for a newborn.

The need to calculate the duration of pregnancy by week occurs in almost every pregnant woman and more than once during pregnancy. And this is necessary not only to simply know your due date or to correctly track the pregnancy calendar. I also want to calculate the duration of pregnancy and childbirth so as not to doubt the correctness of the doctor’s actions; if a mistake is made in the consultation, this can also affect the date of going on maternity leave; I don’t want to work an extra couple of weeks, do I?

First, some general information.

Our calculator will help you calculate the obstetric gestational age; it slightly does not correspond to the real life span of the fetus. Gynecologists base all their calculations on the date of the first day of the last menstruation, and do not count from fertilization, this is due to the ease of error in the date of conception.

A woman’s ovulation can shift significantly in time, especially if she does not have a regular cycle, and of course, not everyone can know the exact date of fertilization; it is difficult to calculate the gestational age based on ovulation. And the date of the start of the last menstruation is usually known.

We have a special calculator that allows you to independently calculate the gestational age online. He will give you information not only about the obstetric gestational age, but also the date of conception, the age of the fetus, and the date of birth.

The problem may arise if you do not have it regularly. How to correctly calculate the gestational age based on menstruation with an irregular cycle? You need to add up the length of the last 6 cycles and divide by 6, so you get the average duration, this is the number of days and must be entered into the calculator field.

All received data can be easily controlled using other calculation systems.

You can accurately calculate the gestational age (or relatively accurately, as gynecologists believe) using the Naegele formula. It does not take into account the length of your cycle and therefore the result may differ from the period that our calculator gives, but this will certainly coincide with the calculations of the gynecologist: from the first day of the missed period we subtract 3 months and add 7 days to the resulting date. This is your due date. It will not be possible to calculate the gestational age by months, weeks and days, as with our calculator.

If you had an ultrasound, the doctor measured the baby's development indicators. Its weight and the length of the bones make it possible to calculate the gestational age using ultrasound, but this calculation is accurate only in the first trimester; the longer the period, the greater the difference in physical development between different children, and the higher the risk of error in determining the timing of pregnancy.

Almost all calculation methods carry a certain risk of error, which is why only 4% of children are born at the PDA (preliminary due date).

It is better to evaluate the results of calculations in combination (ultrasound, date of last menstruation, first movement and other dates and signs). Still, the due date may fall between 37 and 42 weeks of pregnancy.

Calculate

Pregnancy term calculator

For many women, the feeling of an upcoming or already begun pregnancy occurs before the test shows two lines - that is, even before the actual delay. Scientists cannot yet give an explanation for these true premonitions, but the concept of Early Pregnancy Factor has already been introduced into the scientific lexicon, which describes the chemical reactions of the mother’s body in response to the accomplished conception after just a few hours. Currently, there are already tests for identifying the Early Factor hormone in the female body, but due to their significantly high cost, these tests are not produced on an industrial scale.

On average, birth occurs 10 obstetric months (280 days) after pregnancy, when the baby is ripe for birth. However, it should be noted that 280 days is the conditional number of days of bearing a child. All women's bodies are different, and all babies mature differently in their mother's tummy. Some will need 280 days, while others will be “already ready” in 240 days. Only 2% of newborns are born on a precisely calculated day. Most children are two weeks earlier, or several days later than the appointed time. The duration of pregnancy and childbirth is calculated based on the date of the start of the last menstruation.

If we take into account all the changes that occur with the baby almost every day during pregnancy, and especially the first trimester, then in general these processes in importance and complexity, in depth, can be compared with the birth of a new universe. Every day of the little baby inside you is not just a step, it is a huge leap, a breakthrough forward. The birth of a new life, despite the scale of achievements, does not require any external efforts... everything happens under the cover of secrecy. After all, the woman herself learns that conception has occurred only after some time. Thanks to modern technology, scientists have been able to study a little of the great mystery of birth - where EVERYTHING begins. Enter your data and flip through the pages of the calendar of human life development throughout pregnancy. Believe me, amazing discoveries await you!

Calculator

An ovulation calculator is one of the ways to determine the most favorable days for conceiving a child. After all, conceiving a child, even for a completely healthy couple, is not always easy; if you don’t “get” on a favorable day, then pregnancy will not occur. Some people are luckier and pregnancy occurs quickly, while others have to wait several months. Our ovulation and conception calculator will help you calculate that exact time.

But keep in mind that the results obtained may not be entirely reliable. The female body is very mysterious, and sometimes phenomena that are not entirely clear to medicine occur in it. For example, ovulation can occur towards the end of the menstrual cycle or vice versa in the first third (whereas it should be exactly in the middle). There are often stories on the Internet from women who claim that they became pregnant on days that were absolutely safe in terms of the likelihood of conception. So, an online ovulation calculator should not be considered as an independent means of contraception. It is useful as an additional remedy for some categories of women.

As you know, today the most effective and efficient means of contraception are combined hormonal pills and the Mirena spiral. But, unfortunately, hormonal contraceptives have many contraindications and side effects. And not all healthy women are recommended to take them... For example, if a woman has only one healthy sexual partner, but sex life is not regular - 1-2 times a month, or even less often, then you can use safer methods - spermicides, and on dangerous days, as a supplement, also condoms. Dangerous days can be determined by doing some calculations. You need to know the length of your menstrual cycle. Moreover, if it is irregular, then you must first calculate the average value, taking the last 6-12 months as a basis. Next, we calculate exactly the middle of the cycle. This way we get the approximate day of ovulation. We add a week before and a week after - the so-called dangerous time. Thus, half of the month is “dangerous” for a woman, and half is relatively “safe”. If you don’t want to count on paper and trust software calculations more, our ovulation calculator is at your service - you can calculate favorable and unfavorable days for conception right now by entering some data.

Now about something more pleasant - about planning a pregnancy using an online calendar. Here mistakes are no longer so scary, even if they happen. Using the program presented on this page, you can calculate the days most likely for pregnancy. It turns out there are already 9 of these days, or even more! But with frequent sexual intercourse, the number of viable sperm becomes smaller, which means the chances of conception are lower. Better to save your energy. Therefore, we not only use an online ovulation calculator, but also practice the good old method - measuring basal temperature. If financial possibilities allow, we buy tests to determine ovulation. The onset of ovulation is indicated by an increased (above 37 degrees) basal temperature (taking into account possible factors other than pregnancy that could give such a reaction) and a positive ovulation test. You can also confirm the release of an egg from the ovary using an ultrasound examination. There are also subjective signs, such as increased sexual desire, pain in the lower abdomen or from the ovary and fallopian tube involved in the process, the appearance of transparent, rather profuse vaginal discharge.

If you only had part of the evidence of ovulation, but conception did not occur, do not worry. According to statistics, a very small number of couples succeed in getting pregnant in the first 1-3 months of trying. And doctors generally say that you need to start worrying if pregnancy does not occur for more than 10-12 months of sexual activity without contraception. The fact is that that most favorable day does not happen every menstrual cycle - so, calculating an ovulation calculator is only half the battle. To achieve quick results, psychologists recommend simply relaxing and stopping counting and calculating things, making love in certain positions and according to the clock, etc. Stress has too negative an effect on our body. So if you're in a rush to become parents, just go on vacation and enjoy each other's company! And the printed ovulation and conception calculator will then become for you one of the pleasant reminders associated with the period of planning a baby.