How to calculate the due date

Pregnant mothers don’t know how to calculate the due date. The commonly used method for calculating the due date is to count from the first day of the last menstrual period, which usually lasts forty weeks, which is equivalent to ten months. It is mainly affected by various factors and is not fixed. Some may be premature or late. It is normal between thirty-seven and forty-two weeks. A small amount of bleeding will occur within a few months of conception.

Other factors may cause the due date to be less than 40 weeks. The due date calculation method is difficult to calculate based on the 28-day menstrual cycle. Many women's menstrual cycles are more or less than 28 days, which will lead to some unreasonable due date calculation methods. Any hair growth on the due date is an assumption.

Reverse menstrual calculation This is the most common calculation method. Counting backwards based on 280 days (40 weeks), add 9 (or subtract 3) to the month of the day of the last menstrual period, and then add 7 to the date. For example: if the last menstrual period was on January 15th, then 1 plus 9 equals 10, 15 plus 7 equals 22, and the expected date of delivery is October 22nd. For example, if the last menstrual period is on September 25, then 9 minus 3 equals 6, 25 plus 7 equals 32, and the expected date of delivery is June 32, but June has only 30 days, so

It can be calculated that it should be July 2nd. This reverse calculation is based on a 28-day menstrual cycle and must therefore be modified according to the length of the individual's menstrual cycle.

Pregnancy calendar calculation method: Using the commercially available round or disc-shaped pregnancy calendar, you can calculate the number of weeks of pregnancy and the expected date of delivery by comparing it with the day when the last menstrual period began. This method may differ from the reverse menstrual calculation method by 2 or 3 days.

Calculated based on morning sickness: Most pregnant women will experience morning sickness starting from the 4th or 5th week. When morning sickness starts, add 250 to get the expected date of delivery. However, the onset of morning sickness varies from person to person, so it cannot be considered an accurate method.

The above is the method for calculating the expected date of delivery. Any date between thirty-seven and forty-two weeks is normal. A small amount of bleeding will occur within a few months of conception, which will lead to an error in the expected date of delivery. That is, if the pregnancy is not in the middle stage of the menstrual cycle, there are several common methods for calculating the expected date of delivery: the menstrual calculation method and the number of pregnancy reactions and morning sickness.