Dear Bao Ma, how is the expected date of delivery calculated, and why is it not accurate?

The expected date of delivery itself is estimated, and there is no absolutely accurate time. According to statistics, pregnant mothers who give birth on the expected date of delivery only account for 5% of the total number of deliveries, and the rest give birth two weeks before and after the expected date of delivery.

what do you mean by due date?

the expected date of delivery refers to the expected date of delivery, which is generally calculated by the time of the last menstruation. For example, your last period is February 1st.

month+9 (2+9 = November)

date +7(1+7=8)

then the expected date of delivery is November 8 of that year. This is for pregnant mothers with normal menstrual cycle. If the menstruation is irregular, the calculation can be more accurate according to the results of B-ultrasound.

At the 12th week of pregnancy, that is, at the time of the first file check-up, the doctor will estimate the more accurate expected date of delivery according to the biparietal diameter, femur length and other development conditions of the fetus.

Dear Bao Ma, how is the expected date of delivery calculated, and why is it not accurate?

both my babies were born on the 37th week, just full-term. My sister's baby was born at 41 weeks. The two sisters were a month apart, but they were all healthy full-term babies. Therefore, the date of the expected date of delivery is not so accurate, which is specifically affected by the following aspects.

v menstrual cycle is different: each woman's menstrual cycle is different, usually between 28 and 3 days. Some women may be more than 3 days, and some are less than 28 days. For example, I am once every 25 days, and every time it is very regular, so the baby's birth date is also advanced.

when the next period comes, 14 days is the ovulation date. If your menstrual cycle is longer, the ovulation date will be postponed and pregnancy will be later.

v The development of the fetus is different: the development status of the baby during pregnancy is not all the same. Some babies develop fast, while others are relatively slow. These are related to the nutrition during pregnancy and the development speed of the fetus itself, and are also the main reasons for the different expected delivery time.

v pregnant mothers' own situation: during pregnancy, some pregnant mothers have stable mood, regular work and rest, healthier diet, and the fetus can get enough nutrition and develop better.

In addition, the activity of pregnant mothers will also affect the delivery time. Some mothers often exercise, have good physical fitness, open their pelvis quickly and give birth earlier. I'm pregnant with Dabao for 9 months, and I'm still at work. I often do housework at ordinary times, and I have a good baby.

what should I do if the expected date of delivery is advanced or backward?

for myself, I gave birth at 37 weeks, which was actually more than half a month earlier. From a medical point of view, it is normal as long as the fetus gives birth at 37~41(+6 days) weeks. If it is delivered before 37 weeks, the baby is premature. However, babies born after 28 weeks generally have a survival rate of 95%.

Pregnant mothers with signs of premature delivery should be hospitalized as soon as possible, and prepare articles for labor, reduce activity and stay in bed.

Don't worry if you haven't given birth before the due date. Some babies are slow-witted, and childbirth itself is a natural process. Pregnant mothers can continue the prenatal examination, shorten the interval between each examination, and at the same time do a good job in fetal heart monitoring and understand the healthy environment in the uterus. As long as these are normal, they can continue the pregnancy.

You can also walk around more, which can help the fetus enter the basin faster and make the delivery date come faster. Of course, we should also prepare the articles to be delivered, put them in a conspicuous position, and instruct our families. If there are signs of labor (see redness, water bursting, regular contractions), we must pay close attention to hospitalization for labor.

In short, the expected date of delivery is not the standard time. Pregnant mothers should develop good living and eating habits, and do birth check-ups on time. The baby will meet you at a specific time. Not too early or too late, just that day. Dear Bao Ma, how is the expected date of delivery calculated, and why is it not accurate? Why is the due date calculated by my own doctor inaccurate, but the due date of several of my friends is quite accurate? Is the doctor's calculation wrong?

In other words, pregnancy in October is not dozens of months from the first day, and there is no way to determine the possible pregnancy date. In medicine, pregnancy in October is not divided, but the whole pregnancy is 4 weeks. Pregnant mothers use "week" as the calculation cycle, such as the calculation method of 14 weeks and 2 weeks of pregnancy, to remind pregnant mothers what to do or pay attention to at this time or in the next few weeks.

For the accuracy of the calculation results, we take the 4-week pregnancy as the calculation base. We need to know that not all pregnant mothers will be pregnant until the 4-week pregnancy, which is very small. As long as the intrauterine baby is a full-term baby after 39-41 weeks of intrauterine development, the baby born during this period will not have any influence and discomfort, and all the physical functions and brains have been developed, which is a full-term pregnancy.

the 4-week pregnancy is not counted from the first day of pregnancy, but from the end of the last menopause. Because the last menstruation is the only correct date that the pregnant mother can determine, although we can determine the ovulation date through the test, the existing technology cannot determine the time when sperm and eggs combine, because this process will even last for 2-6 days to combine with each other, and their combination is a very complicated reaction, which is difficult to describe, so the last menopause date is used to calculate the start date of pregnancy.

Usually, the pregnancy is 4 weeks. When checking and confirming the pregnancy, it has been about 2 weeks since the pregnant mother was really pregnant, so in the final delivery, she is actually only 28 weeks pregnant, because the first 2 weeks have been included in the calculation, even if the pregnant mother is completely unaware of it.

It should be noted that if the pregnant mother is a woman with irregular physiological cycle, it is not very accurate to determine the expected date of delivery with the last menstruation. Although simple calculations can be made through basic mathematical methods, the accurate determination of the expected date of delivery can still be referenced by the results displayed by B-ultrasound examination. This examination needs to be carried out in the sixth to ninth week of pregnancy, because at this time, the embryo size can be determined by B-ultrasound examination, and the uterus size of the pregnant mother can be checked, and these data will be the pregnant mother's. Tips for tadpole mothers

Pregnancy is a matter for two people, but it takes at least three people's efforts to ensure the baby's safe and healthy growth and development until delivery. The pregnant mother, the prospective father and the doctor have completed nearly half of the pregnancy tasks, so if the pregnant mother has any discomfort or doubts, she should consult the attending doctor and get professional advice and help. How to calculate the expected date of delivery

The expected date of delivery is very important, but many pregnant mothers don't know how to calculate the expected date of delivery. Today, I will tell you how to calculate the expected date of delivery.

I. Introduction to the expected date of delivery

The expected date of delivery is the expected date of production. First of all, understand the next pregnancy: the maternal pregnancy is 1 months, 28 days a month, which means that the whole pregnancy is 28 days and 4 weeks.

II. Calculation method of expected date of delivery

Calculate according to the last menstrual period

Expected month = month of last menstrual period +9 (or -3)

Expected date = date of last menstrual period +7

that is, month +9 or -3, and date +7

For example: < p

if the last menstrual period is February 3rd, 212, the expected month =2+9=11, the expected date =3+7=1, that is, the expected date of delivery is November 1th, 212.

I'm a help mom, a senior nurse, and I personally believe in "parenting" to help you solve the problems on the way with the baby ~

From the word "expected date", we should also understand that although this is based on scientific physiological prediction, it is not completely accurate, at least it should not be accurate to "day". Take the weather forecast as an example, it is also based on scientific prediction, but sometimes it is really inaccurate. According to scientific statistics, the probability of a child born on the due date is generally only about 5%. First of all, how is the expected date of delivery calculated?

General obstetricians' calculation method starts from the first day of the last menstruation: year +1, month-3, date +7,

or year+1, month+9, date +7.

for example, if the date of the first day of your last menstruation is October 1st, 218, then the expected date of delivery calculated according to the above two methods is July 8th, 219.

Of course, many pregnant women may not remember the specific time of their last menstruation. Doctors usually ask about an approximate month, the time of early pregnancy reaction, or calculate an approximate expected date of delivery according to the results of B-ultrasound examination. Therefore, these many factors will lead to the expected date of delivery is not very accurate, and it is generally a rough calculation. And as I said before, according to statistics, the probability of a baby born on the expected date of delivery is only about 5%. Let's briefly talk about the length of pregnancy and some common sense about full-term babies.

Generally, the whole pregnancy is about 4 weeks, about 28 days, and the expected date of delivery is based on the standard of 4 weeks, which is what pregnancy in October means. It can be regarded as a full-term baby from 37 weeks to 42 weeks. In fact, many pregnant women's expected date of delivery can be accurate to one week. Many mothers around me are in this situation, and some can even be accurate to the sky. However, both of my babies were born with a little big deviation in the expected date of delivery. When Dabao was born, the expected date of delivery had not moved for a week. Later, there was a decrease in amniotic fluid during the prenatal check-up. I was hospitalized for three days to induce labor, but I failed to give birth naturally. Finally, I had a cesarean section. Erbao had a cesarean section at 38 weeks. When I was in hospital at that time, I also met many babies who were born after the expected date of delivery and were finally born by inducing labor. In fact, as long as the baby is born one or two weeks before and after the due date, it is normal and generally healthy, so our mother doesn't have to worry too much about the accurate due date.

The main factors that affect the inaccuracy of the expected date of delivery are as follows:

First, the last menstrual time provided by pregnant women when filing in the hospital is inaccurate, which leads to the deviation of doctors' calculations. In fact, many mothers, especially those who are pregnant unexpectedly, may really forget the specific time of their last menstruation, and provide doctors with an approximate time when setting up a file in the hospital, so it will cause some time deviation.

Second, the menstrual cycle of pregnant women is irregular, and the length of the cycle is different, which leads to inaccurate calculation of the expected date of delivery. The algorithm of calculating the end of menstruation is calculated according to the average menstrual cycle of 28 days, so if the menstrual cycle of pregnant women is irregular, it will also lead to the deviation of the doctor's calculation.

Third, the physical quality, mood and other uncontrollable external factors of pregnant women will also lead to the deviation of the expected date of delivery. For example, some pregnant women may affect the fetus because of anger or some unexpected factors when they are near the pregnant period, leading to the early birth of the child. Matters that pregnant women should pay attention to and some things that need to be prepared when the due date is approaching.

First, pregnant women must follow the doctor's advice and have a checkup on time when the expected date of delivery is near. It is particularly important to check the baby's fetal heart rate and amniotic fluid, especially the checkup within half a month of the expected date of delivery. You should always pay attention to your baby's fetal movement. As long as there is abnormality, go to the hospital for examination. When I gave birth to Dabao, I suffered a big loss because I didn't have a prenatal check-up on time. I had a prenatal check-up a few days before the due date, and the doctor said it was normal and asked me to check it again three days later. After three days, I felt all right. I felt that the expected date of delivery was coming soon anyway, and I lived next to the hospital. If anything happened, I went to the hospital directly. Then several days passed, and nothing happened until the expected date was almost a week later. Hurry to the hospital for examination. The doctor said that the amniotic fluid was less and should have come earlier. Why are you so worried? Later, I hastened to induce labor. After three days, the baby failed to give birth naturally and had a cesarean section.

Second, natural delivery is advocated in medicine now, and natural delivery is given priority. A natural baby may be healthier, and the mother will recover quickly after delivery, so the mother who wants to have a natural baby can climb the stairs more appropriately, take a walk outdoors after meals, and don't go to crowded places to bask in the sun properly.

Third, the expected date of delivery is approaching. If you find redness, water bursting or regular pains in your lower abdomen, you need to go to the hospital quickly. These are all signs that your child may give birth.

Fourth, pregnant women with near due date should prepare for bags just yet with their families. Generally speaking, bags just yet can start preparations one to two months before pregnancy and delivery. Bags just yet generally includes mother products and baby products. At that time, many of our items to be produced were found online. Let me pick a few important ones. For example:

1. Breast pumps and disposable milk storage bags. The breast pump is really useful. It is a very painful thing for mother to raise milk after delivery. The breast pump can help mother lactagogue very well, and it is recommended to buy an automatic one, otherwise it will kill people. Postpartum colostrum has a high nutritional value and contains various immune proteins and antibodies. Novice mothers must remember that the milk within 4-5 days after delivery is called colostrum, which is very precious. If you can't drink it, you must temporarily store it, otherwise there will be no such store after this village. Therefore, when you are in the hospital, you should prepare some milk storage bags, store the mother's colostrum a few days ago, and then slowly give it to the children.

2, breast-feeding underwear, and anti-overflow pad. These are really useful, especially when breastfeeding in winter, and it's easy to get wet by overflowing milk, so this is also necessary.

3. Binding straps, postpartum disposable mattresses and thickened sanitary napkins. These things are also very useful in mother's postpartum recovery and postpartum care.

4. Baby's changed clothes, bottles, kegs of milk powder, quilts, diapers, etc. It is better for a baby to change clothes into a jumpsuit, which is more convenient for children to take a bath and change clothes. Within 24 hours after the baby is born, the mother usually has no breast milk and needs milk powder to make a transition, so milk powder bottles are needed.