For many expectant mothers, in fact, they don't know much about the calculation method of the pre delivery period. Do you know how to calculate the pre delivery period? What is the correct calculation method of the pre delivery period? Generally speaking, if a woman does not have normal menstruation for more than ten days, she can be judged as pregnant. Its calculation method is that it can be judged as 40 days pregnant.
In medicine, the first day of the last menstruation before pregnancy is regarded as the start time of the pre delivery period, that is to say, from the first day of your last menstruation to the next 265 days belong to the pregnancy period. In fact, in most cases, pregnancy time can only be a rough calculation method.
For women who have sex and do not take appropriate contraceptive measures, if they do not have menstruation for more than 10 days, they should go to the hospital to check whether they are pregnant. Generally speaking, you can know how many weeks you are pregnant by B-ultrasound.
It should be said that for pregnant women, as long as they remember their last menstrual period, they can calculate the relevant pregnancy time according to it. But if you can't remember your menstrual cycle clearly, or your menstruation is abnormal, how to calculate it?
In fact, expectant mothers can also calculate the time of pregnancy through the following small methods.
1. Fetal movement: normally, there will be fetal movement 18 to 20 weeks after pregnancy, and if it's the first time to give birth, it's the first time to feel the fetal movement, and then add 20 weeks to the delivery date. If it has been produced many times, it is generally necessary to strengthen the number of fetal movements by 2 weeks. Of course, this is just a rough calculation method.
2. Pregnant vomiting: under normal circumstances, if there is pregnant vomiting, it will appear in the last menstruation 42 days, which means that you have been pregnant 42 days, because most women will have pregnant vomiting after 6 weeks.
3. B-ultrasound: I think the calculation method of B-ultrasound is the most accurate. It can determine the double-sided diameter of the fetus through the measurement method, and calculate the size of the fetus through the long meaning of the femur.
Usually, the due date will be increased by 9 in the month of the last menstruation and then decreased by 3. For example, if your last menstruation is in January, the due date is July of the next year.
If you want to calculate the number of days more accurately, you need to see when the first day of the last menstruation is. You can use that number of days plus 7. For example, if it's the 20th, then it's about the 27th of July the next year.
Of course, at present, there is no way to calculate exactly which day the fetus will be born. Under normal circumstances, it is a normal phenomenon to advance two weeks or postpone two weeks. If the delivery is more than 2 weeks ahead of schedule, that is 38 weeks, it is premature. If there is no sign of delivery after 2 weeks, it is also necessary to check in the hospital in time to find out what causes the delay of delivery.
Finally, I would like to remind all expectant mothers that they must take good measures to protect the fetus after knowing that they are pregnant. In particular, they should pay attention to avoid eating some foods that may affect the development of the fetus. At the same time, they should not blindly take some drugs, reduce to places with more radiation sources, and cooperate with various birth tests, so as to be more conducive to eugenics and eugenics.