How many days from conception to childbirth? How to determine the date of birth?

Pregnancy is at the same time the most beautiful, exciting and responsible time. It is pregnancy that teaches a woman to wait. Wait for the most wonderful and magical moment - moments of meeting with your baby. I want to "be fully armed" and prepare for it in advance. Therefore the question: "How many days from conception to childbirth?" - interests every future mother. Some pregnant women bother the doctors with this question, but in response, even the most experienced gynecologists are only getting their hands up. They are doctors, not fortune tellers. And they are responsible for their words. And nobody can name the exact date of birth.

PDR - estimated date of delivery

The estimated date of birth (PDR) can be calculated by yourself. Just remember that any forecast in this case will be only indicative. Be prepared for the fact that your main date with your son or daughter (and maybe twins) will happen for a couple of days or even weeks earlier or later than the date you received during the calculation.

Consider the most popular ways to calculate how many days from conception to childbirth you have to wait.

Pregnancy and its stages

Before calculating PDR, it is worthwhile to understand and understand how a child develops from conception to childbirth and how much pregnancy lasts on average.

According to statistics, in 80% of cases the duration of a healthy pregnancy is about 38 weeks. It's about 266 days. It would seem, here it is! The time from conception to delivery is 38 weeks. What is there to consider? But the main problem is that very few people can accurately call this very date of conception.

Each week of pregnancy is a new stage in the life of the baby. Let us briefly consider what awaits a woman from conception to childbirth for weeks.

Pregnancy from the first to the twelfth week

About what awaits a child, a woman will find out after a delay in menstruation. But by that time, changes had already taken place in her body. The fertilized egg found its place and attached to the walls of the uterus.

In the third week of pregnancy, a zygote (a fertilized egg) counts already 32 cells and begins its movement through the uterine tube into the uterus. The placenta is formed - the connecting link between mummy and baby. With her help, the whole pregnancy will receive food.

From 4 to 7 weeks, there is an increased growth of the embryo. This time for "laying the foundation" of a new person - the nervous and circulatory system, the skeleton, the heart and the brain are formed. The growth of crumbs by the beginning of week 8 is up to 13 mm. On ultrasound, you can distinguish his features. The process of formation of sexual organs, hair and nails begins. The embryo begins to move.

Pregnancy from the thirteenth to the twenty-sixth week

A characteristic feature of the second trimester is the active growth of the embryo. The reproductive system begins to be laid-the girls develop ovaries, and the boys form the prostate gland.

The movements of the embryo become clear and coordinated. From the 17th week the fat layer on the fetal body develops, which participates in metabolic processes. By the 20th week the baby has completely formed the brain, limbs and senses. The skin of the embryo begins to thicken, a lubricant appears on it, designed to protect the tender skin of the newborn.

On the 25-26th week the growth of the crumb grows so much that it becomes cramped. The future mommy during this period begins to feel active tremors and movements of the baby in the abdomen.

Pregnancy from the twenty-seventh to the fortieth week

From the 27th week the third and final stage of pregnancy starts. How many days of pregnancy is left and what does the baby do in the mother's abdomen? How is he getting ready to meet Mom and the world? All these thoughts revolve unceasingly in the head of every future mother.

The kid does not think about it. He at this time actively gaining weight, begins to open his eyes and distinguish sounds outside his "house". Active fetal brain growth continues. The subcutaneous fat layer in the crumb has already fully formed.

From 31 to 33 weeks, the proportions of the fetus change - the head ceases to exceed the trunk, the facial features become more pretty. Such active shifts, as in the second trimester, Mom does not feel any more. This is due to the fact that the crumb often sleeps and can even dream. The epithelium of the fetus is smoothed out and acquires a pinkish hue.

The main task of the mother's body at the final stage of pregnancy is to help the child gain weight. In his lungs, the development of surfactant - a substance that will help the lungs of the newborn to open and make the first sigh in his life begins. Thus, by the 40th week the crumb is ready for life outside the maternal tummy.

In the table below, future moms can determine which tests and studies, as well as new sensations from communicating with the baby, are waiting for them at every stage of pregnancy.

Gestational age	Characteristics of the stage	Necessary research
From the tenth to the thirteenth week	The end of the embryonic period, the formation of the central nervous system.	Double test (free beta hCG and RAPP-A). Carrying out screening for the risks of developing Down's Syndrome and Edwards Syndrome.
From the sixteenth to the eighteenth week	Formation of the reproductive system of the fetus, fatty layer.	Triple testing (alpha-feto protein, chorionic gonadotropin and free estriol), biochemical screening of Down's syndrome and Edwards syndrome, as well as neural tube defects of the fetus.
Eighteenth week	Feeling of the first tremors of the embryo in women who have already given birth.	-
Twentieth week	Sensations of fetal movement in primiparous mothers.	-
Twenty-second week	Ends the formation of the brain and sense organs.	The second ultrasound for the measurement of fetal organs.
The twenty-fourth week	Thickening of the endometrium layer, the formation of original grease.	Dopplerometric analysis is the determination of blood flow in the placenta.
Twenty-sixth week	The baby noticeably increased in size and is cramped. Therefore, Mom increasingly hears his jerks and spinning.	O'Sullivan test or glucose-tolerant testing (to exclude the development of diabetes in the fetus).
The twenty-eighth week	The second term is over. There is a risk of gestosis or late toxicosis in pregnant women.	Prenatal leave registration
Thirtieth week	Pushing crumbs is less and less, since he spends most of the day in a dream.	Mom goes on vacation
Thirty-second week	The development of surfactant - a substance that helps crumbs to take the first breath	Third ultrasound for determining the condition of the placenta and baby
Thirty-eighth week	Completed pregnancy	Mom prepares to meet with the baby

Now that we have got acquainted with the stages of pregnancy from conception to childbirth, and we know what happens to the baby inside my mother's belly, let's try to predict the date of the meeting with him.

Option one: date of delivery on the day of conception

The effectiveness of this method is controversial. This is due to the fact that women rarely know the day of conception. But doctors know for sure how many days from conception to childbirth takes place on average. This is 280 calendar days. Therefore, if you can name the day of fertilization, then it is not difficult to calculate the date of birth. Add to the date of conception 280 days and get the desired result.

The possible error in the calculation of PDR on the day of conception arises from the fact that pregnancy does not necessarily occur on the day when there was a sexual act. After all, the sperm, while in the vagina, retains its ability to fertilize for several days. The discrepancy is possible in two or three days. Therefore, the calculated date of birth is indicative.

Option two: the date of delivery for ovulation

Many people use the method of calculating the date of birth for ovulation. The calculator does not suit everyone. After all, ovulation is monitored by tests or a basal temperature chart only by women who are trying to become pregnant for a long time.

The approximate date of ovulation falls on the middle of the cycle. For example, if the menstrual cycle is 28 days, then ovulation should be at 14. By this date, the middle of the cycle and add 280 days, getting the estimated day of the baby's birth.

The accuracy of this technique is possible only if there is a diary of ovulation and confirmation by tests.

Option three: the date of delivery according to the terms of the last menstruation

This method helps to calculate the date of birth by the date of the last month. Such term of pregnancy is called obstetrical, and usually it is more than the real term of pregnancy.

There are two options for calculating the date of birth by the date of the last month:

1. Using the formula of Nehiel. For this, it is necessary to recline 3 months from the date of the beginning of the last critical days, and then add 7 more days.
2. By the start date of the last monthly period, 40 weeks (or 280 days) are added. Many practitioners-gynecologists resort to this practice.

Despite the popularity of this technique among obstetricians and gynecologists, its accuracy leaves much to be desired. Especially if a woman's menstrual cycle does not correspond to the average standard (less than 28 days or more than 30). How many days of pregnancy will last depends on how long her menstrual cycle is of the standard 28 days. Each additional day of the cycle prolongs pregnancy for 1 day. But no more than 5 days in total.

For women with a violation of the menstrual cycle, this technique is not suitable at all. Popularization of the method among professionals is connected with the fact that a much larger number of women can name the day of the last menstruation than those who can report the day of ovulation or conception.

Often the calculation of the date of delivery by the date of the last month is erroneous due to the abundant implantation bleeding, which indicates the attachment of a fertilized egg to the uterine wall. Many women take it for critical days, and the count of the period of birth begins not from that date.

The prospective obstetrician-gynecologist can determine the expected date of delivery based on the date of the visit to the women's consultation. You can confirm the pregnancy with a doctor as early as 4 weeks. By this date, a total of 36 weeks are added conditionally. The use of such calculations now becomes irrelevant due to the development of the pharmacy industry, which proposes to establish the presence of pregnancy at home with the help of tests. An increasing number of women prefer this method of pregnancy. And on the account in ZHK (female consultation) on pregnancy become later.

Option four: the date of birth by moving

Another option allows you to calculate the date of birth for the fetus, that is, starting from the date when this happened for the first time. Usually, in primiparous mothers such a stir is felt, starting from the 20th week of pregnancy. And for women who are preparing to become a mommy for the second time and more - from 18 weeks. Adding to the original date for as many weeks, we get the desired birth date of the baby.

This, perhaps, is one of the most ancient ways of calculating the date of birth of a crumb. In the absence of an ultrasound machine, it was considered not only the most reliable, but also practically the only one. Using this method of calculation, it is worth remembering the following:

1. The first movements of the embryo in the uterine cavity are fixed for 12 weeks of pregnancy, but they are so weak that the future mother does not notice them.
2. Much more "sensitive" to the tremors and wiggling of the fetus are thin moms, leading a sedentary lifestyle. Such women are able to feel the wiggling baby, similar to a slight tickling, for another 14 weeks of pregnancy. And plump women are less sensitive in this matter.
3. A woman, pregnant for the first time, simply does not know exactly how the embryo moves. As a result, they often do not attach importance to light turns of crumbs in their tummy. Women who already have children are more experienced, and therefore notice them earlier.
4. Visibility of the first movements of the embryo is also due to the thickness of the walls of the uterus. And this is a strictly individual parameter.

If a woman is registered with a woman's consultation, her gynecologist will ask and add information about the first stirring of the fetus.

Variant the fifth: date of labors on US

The most truthful answer to the question: "How many days from conception to childbirth?" - will give an ultrasound study. Using an ultrasound machine, a specialist can determine the size of the fetal egg, according to which the gestation period is calculated.

From the 12th week of pregnancy, ultrasound measures the dimensions of the baby's body parts. But it also happens that the date of delivery for ultrasound does not coincide with the embryonic period of pregnancy. Sometimes the difference of these values is up to two weeks. Such mismatch leads future mummy into confusion and makes them nervous. She is afraid of the wrong development of the fetus or frozen pregnancy.

However, there is no cause for concern. It is rather difficult to interpret the results of ultrasound. Often the old ultrasound apparatus or an inexperienced doctor can "lubricate" the picture. In addition, the development of crumbs is individual and does not always coincide with the generally accepted standard. But if Mom hears from the doctor that the fetal head corresponds to the 23rd week, and the heart 26, it is better to seek advice from another specialist and conduct a new ultrasound procedure.

According to doctors, the most accurate picture of pregnancy on the apparatus of ultrasound can be seen before 12 weeks. This is due to the fact that the stages of development of the fetus during this period are most obvious. And from the 13th week the development of each crumb goes according to its own scenario. Someone is developing slowly and gradually catching up with standards. Another rushes to meet with Mom and ahead of all the terms.

When decoding ultrasound screening specialists correlate the obtained data with the tables of the fetal parameters. Do not fall into depression if the obstetric and embryonic gestation period does not coincide. This is not a pathology, but a kind of norm.

The most truthful is the forecast of the date of delivery with the greatest number of known data. But if you can not exactly name any - it's not scary. After all, the best things in life happen all of a sudden! And the birth of the long-awaited baby is no exception! What does it mean a couple of days of waiting compared to the joy of meeting with your baby and the opportunity to show him this world ?!