How to calculate the date of birth independently? Table for calculating the date of delivery

The article describes all available ways to independently define the dates of the upcoming birth.

Emotional coloring News about the expectation of the kid begins to gradually lose its brightness and intensity characteristic of the first days, and you return to a more or less normal state. The first thing that usually comes to mind: find out when the crumb will appear.

This is a completely natural desire due to both practical purposes, and simple human curiosity:

• for someone interesting month of year to start buying appropriate clothes for the baby
• someone is important to choose the name of the child according to the laws of astrology or church calendar
• for some, the estimated date is needed for spouse vacation planning

Causes can be different, but information about when a woman is prepared for childbirth is interested in many future mothers.

Closer to the end of the third trimester, women begin, as a rule, to calculate the estimated date by all possible methods, rechecking it again and again, as they feel severity and fatigue, and they will not wait to meet with their baby as soon as possible.

How to correctly calculate the date of birth? table

time of birth

Almost every person knows that nine months need to be nine months. But how to count them correctly:

• from what day is sexual intercourse, ovulation, conception, implantation, last menstruation?
• months to take calendar or conditional for 30 days, how many days are exactly in them?

When the future mother faces a pregnancy for the first time, the period of nine months seems to be something very uncertain, and to calculate the date of birth as close as possible to reality, it is desirable.

The generally accepted method for determining the estimated date of birth (hereinafter referred to as the PDR) in order to control the development of the fetus and the pregnancy as a whole is the countdown from the date of the beginning of the menstrual cycle.

PRD \u003d date of menstruation + 280 days (or 40 weeks)

This method establishes the conditional borders of pregnancy, referred to obstetric periodwhich becomes a guidance for doctors and future mothers to observe the development of the baby. When a woman ask a question, at what it is a deadline, pregnant will call the obstetric week of pregnancy.

In fact, true pregnancy occurred later the date of the last menstruation for about two weeks, accordingly she lasts less obstetric period.

Why does the medical community resort to such a strange method of counting the pregnancy by day when it is still only in plans for potential parents? To search for an answer, we will briefly consider that and what time it takes place in the "pregnant" cycle of a woman:

1. no matter when proximity occurred, fertilization or conception will occur on the day of ovulation, and taking into account the vitality of spermatozoa, the difference between these moments can reach up to 5 days
2. ovulation takes place on average 14-15 days before the end of the cycle (next menstruation), but may come before (in 16 days) and later (for 12-13 days)
3. the conception does not guarantee pregnancy, for this, a fertilized egg must attach to the uterus, or implanted that it takes 6-8 days on average, but can also vary in time

IMPORTANT: 80% of cases of conception end in unsuccessful implantation, that is, pregnancy does not occur, but a woman doesn't even know about it, because the monthly occurs on time.

So, the point of reference to pregnancy is very difficult, due to the fact that it depends on several individual factors:

• cycle duration
• ovulytion Day
• duration implantation

fetus

Even theoretically accurately knowing the date of the occurrence of pregnancy, it would not guarantee the definition of the date of delivery a hundred percent, since the beginning of the generic activity is also determined by many factors, including:

• physiological readiness of the kid
• character of pregnancy
• age and health of mom
• number of preceding pregnancies

For these reasons, doctors do not set their goal to accurately calculate the true date of conception and implantation. In addition, most women remember when they had the last menstruation, and what is ovulation, and in what time it takes exactly them, they know not many.

Therefore, it is much easier to count down from the beginning of the cycle. This makes several assumptions:

• cycle duration 28 days
• ovulation occurs after 14 days (on the 15th day)
• the implantation periods fall within the boundaries of the norm.

If you fit into the specified parameters, you can safely search in the table below the date of the intended meeting with the baby. Nobody guarantees exact probability, but this is the maximum time limit.

table to determine the date of delivery

• in the column on the left, you should find a month in which you had a menstruation last time (in black with an asterisk)
• next, find the number in the line with this month (marked with black), the corresponding date of the beginning of the last menstruation
• under it, the estimated date of birth and month will be indicated (marked with raspberry)

Examples shown in the table:

1. at a woman with the first day of the last menstruation on March 28, the birth is planned on January 2
2. if the start of menstruation was accounted for August 11, the replenishment should be waiting on May 18

If your cycle is slightly different, the table will also be a good guideline, but you need to be prepared for the fact that the breakdown in 1-2 weeks is considered an option for the norm. In other words, from the point of view of medical science, ideally, pregnancy is 40 obstetric weeks, but more often falls in the range of 38-42 weeks.

Important: According to the latest data, the norm relates to the variation between pregnancy in 37 days or 5 weeks. Previously, this indicator was 4 weeks (\u003d 42-38).

How to calculate the date of birth of ovulation?

definition of PDR

Cases are possible when a woman knows exactly the day in which she has occurred ovulation. This is usually characteristic of women, for a long time planning pregnancy.

For example, ovulation has become known with:

• Ultrasound, which woman did several times during a cycle for monitoring ripening and exit an egg
• ovulation test, which shows a positive result for 24-36 hours before ovulation
• graphics of basal temperature
• own explicit sensations due to long-term observations of their organism

In these circumstances, I want to learn the DA more precisely, especially if the cycle does not suit the ideal and total duration, and by the number of days in the second phase. The formula for calculating the day "X" in this case looks like this:

PDR \u003d date ovulation + 266 days (or 38 weeks)

This time is called embryonal. If you compare these numbers with the traditional formula described above, the difference is 14 days (\u003d 280-266). It is, on the 14-15 day of the cycle comes ovulation in the middle cycle of 28 days.

Recent studies of the US National Health Institute concluded that the pregnancy is more often 268 days from the date of ovulation (and not adopted 266), that is, 38 weeks and 2 days. The duration of the gestational period also depends on how much time it takes the implantation of the fetus in the uterus. The moment in the study was recorded on the first day of the growth of HCG.

Important: It was also established that the duration of pregnancy affects the age of the mother and its birth weight. The older the woman and the more her weight is at birth, the longer the period of gestation will be.

How to calculate the date of birth by the date of conception?

waiting for childbirth

The conception or fertilization occurs at the time of the sephematozoa and egg meeting. Due to the fact that the egg cell comes out of the follicle once a month (normally), which is referred to as ovulation, and retains the ability to create a new life only 24-36 hours, meeting with sperm and conception usually occurs on the day of ovulation or the next day.

Thus, the date of conception and the date of ovulation often coincide or differ only on 1 day. In this regard, the principle of calculating the DTR by the date of conception is similar to the method based on the ovulation date described above.

Important: It should be distinguished by the day of sexual intercourse and the day of conception. The difference between them can reach up to 5-7 days, depending on the life expectancy of the spermatozoa of a particular man.

How to calculate the date of birth exactly in a month?

Supporting date of childbirth, which a woman will announce a gynecologist, as mentioned above, is based on the data on the last menstruation. At the same time, the value of the start of the cycle, that is, the date in which the last menstruation began, the duration and date of the end of the role does not play.

In order not to count 280 days from this date, there is a simpler method (Nemelet formula):

PDR \u003d date of menstruation - 3 months +7 days + 1 year

Example number 1:

• last menstruation was from 13 to 19 June 2015
• in the estimated date of the beginning of the next cycle on April 10, menstruation did not begin, and the pregnancy test was positive
• to remember Date June 13 (the beginning of the last menstruation), it will be asked for a pregnant woman more than once
• returning 3 months ago, we get March 13, 2015
• i add 7 days, we get March 20, 2015
• we add a year, we get March 20, 2016 - this is the DA

Important: In the formula, subtractable three months are equivalent to 92 days, so if the amount of days in months preceding the month of the last month is 89, 90 or 91 days, not seven, and 4, 5 or 6 days, respectively, should be added.

Example number 2:

• the start date of the last menstruation - December 15, 2015
• we take three months, we get September 15, 2015
• amount of days subtracted months: November (30) + October (31) + September (30) \u003d 91
• consequently, we add 6 days, we get on September 21
• add year, DRD - September 21, 2016

counting

Example number 3:

• menstruation Date - May 2, 2015
• minus for three months - February 2
• the amount of days in April, March and February (not a leap year) - 89
• therefore, add to the result of 4 days
• as a result, DRD - February 6, 2016

How to calculate the date of delivery with an irregular cycle?

As used in medical practice, calculating the date of birth is based on the assumption that the woman has a standard cycle with a duration of 28 days, in which ovulation occurs on 14-15 days.

Imagine the situation:

• date of the last menstruation of women - September 12, Menstruation DRDD - June 19 (September 12 +280 days)
• the day of "X" comes, the generic activity does not begin, the woman begins to worry, and the gynecologist insists on the stimulation of labor, threatening the aging of the placenta
• and only in rare cases, the doctor will inquire the duration of its menstrual cycle
• meanwhile, the cycle of a future mother is 40 days, and therefore, the date of birth on objective reasons is shifted at least 12 days
• ovulation Most likely, it came not on the 14th day, but on the 26th day (\u003d 40-14)

Important: Usually the duration of the second phase of the cycle is stable and is 14 days, that is, ovulation occurs 14 days before the end of the cycle.

• in other words, conception occurred 12 days later than in the standard cycle (\u003d 26-14)
• accordingly, the woman has not yet "overlaps", the duration of true pregnancy has not yet reached 266 days, no reasons for excitement

Thus, it is quite natural that childbirth do not come yet, and the explanation of this is logical: the woman had a late ovulation.

calendar of childbirth

If you are the owner of a non-standard or irregular cycle (more or less than 28 days), it is better to navigate on the date of ovulation, and conduct a countdown from it (add to the date of ovulation 266 (268) days). If the date of ovulation is unknown, follows:

• find the difference between the number of days in your cycle and the standard
• if the cycle is more than 28 days, add the difference to the PDD calculated by menstruation
• if the cycle is less than 28 days, take away the difference from the PDR calculated by menstruation

In the example above:

• the difference is 12 days \u003d 40-28
• cycle more than 28 days
• consequently, more likely date of delivery - July 01 (\u003d June 19 + 12 days)

How to correctly calculate the date of birth according to the first ultrasound?

For more accurate results, ultrasound should be carried out in the first trimester. If you contact too early, on the 4-5 week, that is, immediately after the delay, there is no guarantee that the doctor will even see a fruit egg. Therefore, if there is no threat of ectopic pregnancy, it is possible to record on the ultrasound after 6-7 weeks, and better in the period from 10 to 14 weeks.

With the help of the ultrasound, the doctor will appreciate the Coccico-parmer fetus, according to which you can determine the term of pregnancy.

table: Pregnancy term by CTR

For example, if the fetal CTR is 44 mm, the pregnancy term on ultrasound has 11 weeks and 2 days (or 79 days).

The table indicates an obstetric period. Accordingly, it remained to childbirth 201 days (\u003d 280-79) or 28 weeks and 5 days.

In 2 and 3 trimester, the accuracy of the conformity of the fetal parameters of the pregnancy is significantly reduced, since the future kid begins to gain weight, grow and develop according to individual and genetic features, which cannot be adjusted under any table.

How to calculate the date of birth after Eco?

ECO

• Regardless of how conception occurred: a natural way or in laboratory conditions, the gynecologist will still be focused on the DATD by the date of the last menstruation
• However, one can calculate the embryonic period. During the day of ovulation, the day of puncture takes when a woman took a follicular fluid with eggs. To this date you can add 266 days and get DA
• The same result can be obtained by adding to the date of puncture 14 days, that is, to determine the conditionally the date of the last menstruation, from which the obstetric period will lead, and referring to 40 weeks (280 days)

How to calculate the date of birth according to the first movement of the fetus?

merchants during pregnancy

The movement of the fetus, although it is quite concrete and real, refers to the subjective factor to determine the date of delivery.

The fact is that it is very difficult to determine when the future mother clearly experienced the presence inside a small little man in his shocks and movement. The primary women notice this later than more experienced mothers, they are often confused with the processes occurring in the intestine, they decide to feel something else.

At the same time, as a reference point, this method can be taken into account. For this:

• by the deadline when the movement for the first time felt a primary woman, add 20-22 weeks
• by the date of the first jog, who felt a repeated woman add 24 weeks

Different deadlines are explained by the fact that the first feel the movements only on July 18-20, and the second - from 16 weeks.

But in this method, you can only roughly estimate the period of childbirth. At what point, the woman will fix the first movement, depends on the characteristics of the structure of the uterus, from the method of attaching the fetus to the wall of the uterus, from the sensitivity of a woman and many other factors.

How to calculate the date of the second genera?

There is observation that each subsequent pregnancy is shorter and lighter than the previous one. This is not always the case, and depends on individual characteristics. But often still the second childbirth occur earlier, at 38 week, while the first - on average for 39-40 weeks. Otherwise, the calculation of the PD is similar to the principle of determining the date of the first birth.

second genera

• It is known that the main benchmark for calculating the DA is the last menstruation, but frequent cases when a woman will re-re-with still non-renovated after the first birth cycle
• How to be in this case? Woman does not know the dates of the last menstruation simply because they were not yet after the first pregnancy
• In such circumstances, the term is usually established according to the results of the ultrasound. This is the only most accurate way to determine the term of pregnancy and count the date of delivery. But it is necessary to make it no later than 1 trimester

How to determine the exact date of birth yourself: tips and reviews

soon childbirth

1. If the menstrual cycle is 28-30 days, then the date of birth, calculated in the female consultation (on menstruation), and will be the most close to the truth
2. In case the cycle differs significantly in duration from standard or hesitated once again by more than 3-4 days, report this to the gynecologist when registered
3. In this case, hold in the mind that childbirth can start earlier or later the DA for the number of days on which your cycle is shorter or longer than the standard 28-day
4. Should not be too looped on the calculation of the date of delivery, the percentage of accurate hit is still not high
5. Get ready to morally in advance that childbirth may occur earlier or later than the deadline
6. If the first birth came exactly in the DA, it does not mean that it will also be the case and with the second
7. Remember that the PDR is primarily needed for medical purposes: establishing significant deviations in the development of the fetus depending on the period of pregnancy, assessment of the maturity of the placenta and monitoring other vital indicators in order to timely hospitalize women and stimulating the delivery, if necessary

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