Does pregnancy start or end with the last menstrual period?

Is the delivery date based on when the menstrual period starts or ends? The due date is a time that every expectant mother is curious about. It is also known that in medicine, it is calculated according to the expected date of delivery. So, does the delivery period mark the beginning or end of the last menstrual period? Does the delivery date refer to when the menstrual period begins or ends? ?

1. Does the birth period start or end when the menstrual period ends?

The due date is calculated based on the time when the menstrual period starts.

The due date is the estimated time of delivery of a pregnant woman. The due date is not the exact time of delivery. Experts have analyzed and calculated that only about 5% of women give birth on the due date. Because every pregnant woman cannot accurately tell the time of pregnancy, medicine requires that the expected date of delivery be calculated from the first day of pregnancy. The total pregnancy period is 280 days, or 10 months. Therefore, the delivery date is calculated based on the beginning time of the menstrual period.

2 How to calculate the due date at the beginning of pregnancy

Calculating the due date based on menstruation is also known as "pregnancy due date calculation"

This method of self-diagnosis of due date is very simple and has a relatively high accuracy. It is currently widely used by obstetricians and gynecologists. However, since some women do not understand their menstrual period or have irregular ovulation, the accuracy of the results will be affected. However, if your period is correct, this method is 100% accurate.

How to calculate:

The expected date of delivery is calculated from the first day of the expected date of delivery. The entire pregnancy period is 280 days, 10 gestational months, and each gestational month is 28 days. The calculation method is: 9 or -3 of the expected date of delivery, which is the number of months of the due date, and 7, which is the date of delivery.

For example: if the first day of your last period was February 1, 2014, then the month is 2 9, the time is 1 7, and the due date is November 8, 2014. Or if your due date is April 15, 2014, then the month is 4-3, the time is 15 7, and the due date is January 22, 2015.

Note: This method is suitable for women with regular menstrual cycles, otherwise the calculation results may be inaccurate.

3Other ways to calculate due date

Pregnancy calendar optimization algorithm: Using the commercially available round or disc-shaped pregnancy calendar, you can compare the start date of the last menstrual period to calculate the gestational age and due date. This method may differ from the menstrual period reverse optimization algorithm by 2 or 3 days.

Calculation of ovulation temperature curve: That is to say, take the last day of the ultra-low temperature section of the ovulation temperature curve as the ovulation period, and then push back 264-268 days, or add 38 weeks.

Calculation of uterine fundus height: Starting from the end of April of pregnancy, the height of the uterine fundus changes every month, and the delivery date can be known based on this.

Reverse calculation of menstrual period: Count backwards based on 280 days (40 weeks), add 9 (or subtract 3) to the month of the day when the last menstrual period came, and then add 7 to the time, and you can calculate.

Calculation of morning sickness: Morning sickness usually occurs on the 6th week of pregnancy. The calculation method is: due date = 34 weeks when early pregnancy reactions occur.

4. Note that the due date may not be accurate

To put it simply, the due date is the estimated time when a pregnant woman will give birth. It should be noted that the due date is not the exact time of delivery of the pregnant woman. The due date itself is different from the pregnancy time. In addition, the time of birth of the baby is affected by factors such as the intrauterine environment, the baby's development, the physical condition of the pregnant woman and the actual environment, so the time of birth cannot be accurately predicted. The due date is only the approximate time of delivery of a pregnant woman. The purpose of calculating the due date is to allow pregnant women to prepare for being a mother, not to calculate which day will definitely give birth. If a pregnant woman gives birth later than the due date or before the due date, there is no need to worry too much. Because it is normal for the baby to be born within two weeks before or after the due date.

5 Tips for Healthy Mind and Body

After giving birth, women are anxious to know when the baby can be born. This feeling is completely understandable. Not only the pregnant women themselves, but also their families will plan about when to prepare things for hospitalization. Although the due date can be calculated using some methods, it cannot be guaranteed to be 100% accurate. Therefore, pregnant mothers should prepare delivery items and so on at least half a month in advance, so as to be calm and prevent accidents before they happen.