When is the due date calculated?

The due date is calculated from the day of the start of the last menstrual period, if the day of the start of your last menstrual period is the solar calendar, the due date is calculated by adding nine or subtracting three months and adding seven days. If the day of your last menstrual period starts is a lunar calendar, you can calculate your due date by adding 9 or subtracting 3 months and adding 14 days to your own due date.

Generally speaking, it takes 280 days to get pregnant, 40 weeks to get pregnant, and the due date is calculated from the first day of the last menstrual period, the number of months plus nine or minus three, and the number of days plus seven. If the expectant mother adds fifteen, it is the expected date of delivery of the lunar calendar. The calculation of the due date is only an approximate estimate.

According to the actual situation of the mother, there may be a difference of about seven days. If you usually menstruate, the cycle is short, less than a month, and the days of labor are mostly before the expected date of delivery; If the menstrual cycle is usually long, about 40 days, most of the days of labor are after the expected date of delivery.

The due date is calculated from the first day of the last menstrual period. Generally calculated as 28 days per month, the entire pregnancy period is 280 days, 10 months and 40 weeks. If you can't remember the day of your last menstrual period, you can calculate the due date from the first fetal movement, which is generally 18 to 20 weeks, and then add 20 weeks to calculate the due date.

This is calculated from the first day of menopause.

When is the due date calculated?It starts counting from the month you don't have your period. Calculate to the month is your due date.

It is calculated from the time of the last menstrual period.

When did the due date start to calculate, I think the proof is still scanning, this school can just explain all today, think that it will be effective, the most economical and practical, and say that there is no way to do this, even if all of me may be according to his certificate, it should be possible to make some calculations according to some of the child's production lubrication of the whole certificate, should be his King Kong Town Star is, otherwise it is really possible that the whale is not worth it.

When is the due date calculated?The expected date of delivery is calculated from the first day of the expected date of delivery.

The due date is calculated from the first day of your last menstrual period, and the date of your last menstrual period must be remembered, otherwise, the due date will not be calculated accurately.

What is the expected date of delivery? The expected date of delivery begins on the first day of the last menstrual period.

The due date is not an exact date. Because each pregnant woman has a simple and accurate date of conception, in order to facilitate the estimation and examination in the future. Therefore, it is medically stipulated that the expected date of delivery is calculated on the first day of the last menstrual period of the pregnant woman, and the entire pregnancy period of the expected date of delivery is 280 days, 10 pregnancies.

Each month is 28 days and 40 weeks. Therefore, the due date is calculated from the first day of the last menstrual period of the pregnant woman.

Why should the due date be counted from the last menstrual period?

The due date is from the start or end of menstruation.

How to calculate the due dateThere are many ways to calculate the expected date of delivery, such as calculation based on menstruation, ultrasound calculation, uterine size calculation, morning sickness calculation, and so on. However, the default medical estimate is based on the last menstrual period of the pregnant woman. This method of self-testing of the expected date of delivery is relatively simple and highly accurate, and is a common method used by obstetricians and gynecologists at present.

However, because some women do not know their menstrual time, or the ovulation day is irregular, it will affect the accuracy of the results. However, if your period is accurate, this method can be as accurate as 100%.

Calculation formula:

Add 9 or subtract 3 to the number of months of the last menstrual period, and add 7 days (the day is the first day of the last menstrual period). If you use the lunar calendar, the month is calculated in the same way, and 15 is added to the day instead.

Examples:The last menstrual period starts on March 5 and ends on March 10.

Then the due date is.

Month = 3 + 9 = December.

Date=5+7=12 days.

So the due date is December 12.

Applicable Groups:

However, relying on the last menstrual period to calculate the due date is suitable for women who can clearly remember their last menstrual period and have a stable menstrual cycle of 28 days, which is not suitable if your menstrual cycle is unstable and often delayed or advanced.

It is implemented in many due date calculators on the Internet, or in the expected date calculation books issued by hospitals, which use this calculation method.

Self-test method for expected delivery date.

How to calculate the due date most accurately.

Is the due date accurate?The due date, as the name suggests, is the expected date of delivery. It should be noted that the due date is not an exact date of delivery, because it is difficult for every pregnant woman to accurately determine the time of conception, so it is medically prescribed to calculate the due date from the first day of the last menstrual period. Then the due date itself is different from the date of conception.

In addition, when the fetus will be born is affected by factors such as the intrauterine environment, fetal development, the physical condition of the pregnant woman and the actual environment, and the time of birth cannot be accurately predicted. The due date is only the approximate time when a pregnant woman will give birth, and the purpose of calculating the due date is to prepare the pregnant woman to be a mother, not to calculate which day she will actually give birth on the same day. Therefore, according to statistics, only about 53% of pregnant women will give birth on the day of their due date.

Therefore, the due date may not be accurate.

The expected date of delivery is calculated from the first day of the last menstrual period, and the estimated date of delivery is obtained by subtracting 3 months or adding 9 or 7 to the date.

The due date is 40 weeks of gestation, not all pregnant women will give birth naturally on the due date, it is only an estimated time, and it is normal to have to advance 1-2 weeks and postpone 1-2 weeks. However, it should not exceed 42 weeks, which is the post-term pregnancy, and if the placenta function deteriorates after 42 weeks, the amniotic fluid decreases, and the fetus may have intrauterine hypoxia.

In addition, for women with irregular menstrual cycles, the expected date of delivery cannot be estimated from menstruation alone, and the due date must be verified by early ultrasound. Ultrasound at 7-8 weeks of pregnancy and 12 weeks of pregnancy is more accurate for estimating the expected date of delivery, and the estimate of the expected date of delivery will be more accurate by combining menstruation and ultrasound.

Diet during pregnancy should follow the 12345 principle:

For pregnant mothers, the most scientific and simple diet method is the "diet", that is, to ensure 1 cup of milk, 2 eggs, 3 taels of meat, 400 grams of staple food, 500 grams of vegetables and fruits every day. This method is summarized on the basis of the balanced diet pagoda of Chinese residents, and it can be said that it has achieved the highest level of nutrition during pregnancy: comprehensive, balanced and sufficient.

12345 "On the diet, 1 cup of milk can be milk, yogurt, cheese, or 100 grams of tofu. Meat should be appropriately selected more poultry and aquatic products, and less pork and pork ribs with high fat content should be eaten. Meat intake must be controlled.

Among the 500 grams of fruits and vegetables, vegetables should be the main ones. In particular, eat more red, green, and yellow vegetables and dark yellow fruits, which are richer in nutrients such as iron. Vegetables can replace fruits, whereas fruits cannot replace vegetables.

The expected date of delivery should be 280 days or 40 weeks from the first day of the last menstrual period. There are fluctuations before and after. Calculation method:

Due date month Month 9 or -3 of the first day of the last menstrual period, Date of due date Number of days on the first day of the last menstrual period 7In this way, the calculated time is the due date.

For pregnant women with irregular menstruation, the expected date of delivery can be estimated through the following comprehensive analysis. 1. Inquire in detail about the usual menstrual situation, if the pregnant woman's menstrual cycle is long, the expected date of delivery can be postponed for the corresponding number of days. 2. According to the ovulation date of the increase in basal body temperature before pregnancy, 15 days forward is the expected date of delivery for the last menstruation.

3. The husband and wife live separately, which can be calculated according to the date of the intercourse. 4. Estimated according to the time of the onset of early pregnancy reaction (the 6th week of pregnancy). 5. For those who do ** examination in the first trimester, it is calculated according to the size of the uterus at that time.

6. The time to hear heart sounds is generally more than 20 weeks. 7. B-ultrasound examination, which is calculated according to the gestational week that the measured value is consistent with.

The due date is determined based on the first day of a woman's last menstrual period and the length of her gestational week (i.e., the number of weeks pregnant). Typically, the calculation of the due date assumes that each woman has an equal menstrual cycle length and is 28 days, as this is the most common menstrual cycle length. Therefore, the usual calculation of the due date is:

The first day of the last menstrual period plus 280 days is the due date.

However, in reality, very few women have a menstrual cycle that happens to be 28 days. If the menstrual cycle is shorter than 28 days, the expected date of delivery will be earlier than this calculation; If the menstrual cycle is longer than 28 days, the expected date of delivery will be later than this calculation. If the pregnant woman has determined the day of ovulation (i.e. the date on which ovulation begins each month), the expected date of delivery can be calculated by adding 280 days to the day of ovulation, which is more accurate.

In addition, ultrasound can also detect the size and development of the fetus, which can be used by pickpockets to determine the pregnosis of birth. Usually, the doctor will perform the first ultrasound at 6-10 weeks of gestation, and then enter the measured data into a computer program, which will give a more accurate due date.

In summary, the due date is calculated based on the first day of the last menstrual period and the length of the gestational week. If the length of a woman's menstrual cycle is not 28 days, or if the day of ovulation can be determined, a more accurate method can be used to calculate the due date. Ultrasound is also a reliable way to determine your due date.

Hello: The due date is calculated from the date of the first day of the last menstrual period.

The due date is calculated as the number of months of the last menstrual period plus 9 (or minus 3) and the number of days plus 7.

The last menstrual period was October 17, 2010, and the expected date of delivery was July 24, 2011.

A full-term pregnancy lasts about 280 days (about 40 weeks) and is normal to give birth within two weeks before or after the expected date of delivery.

The due date is calculated according to the solar calendar! The lunar calendar can't be counted yet! It's so smart Many people are confused, they just remember the lunar calendar, and they have to find the perpetual calendar slowly, which is very troublesome

It should be year +1, month -3, day +7

That is, around July 24, 2011, but this is calculated according to 40 weeks of pregnancy, and the baby is born at 37 weeks and 42 weeks of pregnancy is considered normal, don't be too nervous

I wish the baby healthy, beautiful and smart (mom is so smart, the baby can't be wrong).

December 16 of the lunar calendar is January 19, 2012 of the Gregorian calendar, and the expected date of delivery is calculated from the first day of the last menstrual period, and the entire pregnancy period is 280 days, 10 gestation months (each gestation month is 28 days). Pregnant women give birth within 38-42 weeks of gestation, both at term. Since the length of each woman's menstrual cycle varies, it is normal for the estimated due date to differ from the actual due date by 1-2 weeks.

The main calculation methods are as follows:

Calculated based on the last menstrual period:

The month of the last menstrual date plus 9 or minus 3 is the number of months of the expected date of delivery; The number of days plus 7 is the expected date of delivery.

The last menstrual period was January 19, 2012, and the due date was around October 26, 2012.