How to Accurately Calculate the Expected Date of Delivery Based on the Lunar Calendar?

Clinically, there is generally no accurate way to calculate the expected date of delivery based on the lunar calendar. The expected date of delivery is usually calculated based on the last menstrual period, ultrasonography, and fetal movement time, and regular prenatal screening is also required. Here are some methods:

Under normal circumstances, the entire pregnancy cycle is generally 40 weeks, with 7 days considered as one week. If the menstrual cycle is regular, the expected date of delivery can be calculated by adding 280 days to the last menstrual period. One can then refer to a calendar to determine the corresponding date in the lunar calendar.

Ultrasonography is a commonly used examination method. Through ultrasonography, the size of the gestational sac and the changes in the biparietal diameter of the fetus can be clearly observed. Based on the fetal growth and development, the date of the last menstrual period can also be estimated, thereby determining the expected date of delivery.

If the menstrual cycle is irregular or the date of the last menstrual period is unclear, the expected date of delivery can be estimated based on the time of the first fetal movement. Generally, 20 weeks are added from the time of the first fetal movement. However, due to differences in fetal growth and development and the individual constitution of the pregnant woman, there may be some discrepancy between the actual delivery time and the expected date of delivery. If it is already in the late stage of pregnancy, one should always be aware of any changes in the fetus. If there are any obvious symptoms of discomfort, prompt and standardized treatment is necessary.