How is the Expected Delivery Date Calculated?
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The expected date of delivery is generally calculated using the extrapolation method, which starts from the last menstrual period before pregnancy. Subtract 3 days from the month, or add 9 days and 7 to obtain the expected date of delivery. The entire pregnancy period is generally around 40 weeks, which is 9 months and a few days. Therefore, there may be a one-week error between the calculated time and the actual expected date of delivery, which is a normal phenomenon. After all, the specific time of the expected date of delivery will be affected by many factors.
If the date of the last menstrual period is unclear after pregnancy, or the menstruation is irregular every month, in such cases, the expected date of delivery can be estimated through B-ultrasound. Calculations based on the results of B-ultrasound examinations are usually accurate. Through B-ultrasound examination, the length of the embryo can be specifically understood, and doctors will calculate the expected date of delivery based on the B-ultrasound report. The method of using B-ultrasound to calculate the expected date of delivery is more accurate than using the date to calculate the expected date of delivery.
The expected date of delivery is the date when a pregnant woman gives birth. The calculated time of the expected date of delivery is the time when the pregnant woman goes into labor. This result is relatively accurate, but some pregnant women's expected dates of delivery are not that accurate, either earlier or later. These are normal occurrences as everyone's physical condition differs, and the process of pregnancy is affected by various factors, which may lead to inaccuracies in the expected date of delivery.
Calculating the expected date of delivery is to provide pregnant women with an approximate delivery time, allowing them to be prepared and better prepared in advance. The expected date of delivery is merely a reference. It is normal for the expected date of delivery to be earlier or later within a reasonable time frame, and it will not have any impact.