How is pregnancy calculated? How to calculate the pregnancy period

Counting from the first day of your last menstrual period, 280 days after your due date is your due date. People say that they are pregnant in October, and in this October, there are only 28 days per month, I wish you a good pregnancy!

Counting from the day of the last menstrual period: Gregorian calendar: month +9 or -3 days: +7 Lunar calendar: month +9 or -3

Number of days: +14

The due date is calculated.

The calculation of pregnancy is based on the start date of the last menstrual period. In most cases, a menstrual cycle lasts 28 days, but it can be as long as 30-35 days or as short as 21 days. Therefore, an individual's menstrual cycle needs to be taken into account in the calculation of pregnancy.

Usually, your doctor or midwife will use a pregnancy calculator or pregnancy calculator to determine your pregnancy.

In the process of calculating the pregnancy period, it is necessary to pay attention to determining the time of conception. If you have sex and conceive in the next 1-5 days, then the actual results may be slightly different. In general, the start date of the last menstrual period should be accurately determined and the pregnancy period should be calculated in conjunction with the length of the cycle.

After calculating the pregnancy period, the pregnant woman should consult a doctor in time to get accurate advice and diagnosis.

There are many factors involved in pregnancy calculations, including the length of the menstrual cycle, the time of conception, the physiological state of the pregnant woman, and more. In addition, you need to consider how long it will take to have a prenatal check-up, normal pregnancy symptoms and how to live a healthy lifestyle during pregnancy. Pregnant women can consult a professional obstetrician-gynaecologist or midwife if needed.

They can provide appropriate advice based on individual circumstances to ensure health and safety during pregnancy.

In short, the calculation of pregnancy needs to combine multiple factors such as the length of the menstrual cycle, the time of conception, etc., and it is necessary to consult a professional doctor in time to obtain accurate and comprehensive advice. In addition to calculating the pregnancy period, pregnant women should also pay attention to a healthy diet, professional pregnancy physical examination, and actively participate in appropriate maternal yoga activities to protect the health of themselves and their fetus. <>

1. Calculated according to the last menstrual period: the month of the last menstrual date is added by 9 or minus 3 to be the number of months of the expected date of delivery; The number of days plus 7 is the expected date of delivery. For example:

Ms. Zhang's last menstrual period was March 13, 2008, and her expected date of delivery was December 20, 2008. Ms. Li's last menstrual period was May 28, 2008, and her expected date of delivery was about:

March 5, 2009 can also be extrapolated from the first day of the last menstrual period to the 280th day, which is the expected date of delivery.

2. Calculate according to the date of fetal movement: If you can't remember the date of your last menstrual period, you can calculate it according to the date of fetal movement. Usually fetal movements begin at 18-20 weeks after pregnancy. The calculation method is as follows: the day of fetal movement plus 20 weeks for primiparous mothers; In multiparous women, the day of fetal movement plus 22 weeks is added.

3. Calculate according to the basal body temperature curve: take the last day of the low temperature section of the basal body temperature curve as the ovulation day, and calculate 264-268 days backwards from the ovulation day, or add 38 weeks.

4. Estimation according to B-ultrasound examination: The doctor can estimate the gestational age and calculate the expected date of delivery by measuring the diameter between the fetal head and biparietal head, head and hip length and femur length when doing B ultrasound.

5. Estimation from the time of morning sickness: morning sickness generally occurs at the end of 6 weeks of pregnancy, that is, 42 days after the last menstrual period, and the expected date of delivery is calculated backwards to 280 days.

Pregnancy is a prudent thing, because the body is more fragile during pregnancy, so pregnant women must do a good job of nursing, but also regular prenatal checkups, under normal circumstances, pregnancy for ten months, during this period to pay attention to keep warm, strengthen nutritional intake, pregnant women do not do tired housework, to avoid accidents, what are the calculation methods during pregnancy?

1) Ordinary algorithm: from the day you have your period, the estimated date of birth is calculated from the date of your last menstrual period, plus nine or three times, then seven, which is the expected date of delivery.

2) Calculate fetal movements: If you don't remember the date of your last menstrual period. You can make an estimate based on the date of the fetal movement. Usually fetal movements begin after 18 to 20 weeks of gestation.

3) Count morning sickness: The reaction to morning sickness usually occurs on the sixth weekend of pregnancy. This is 42 days after the last menstrual period. So it is calculated as 280 days.

4) B calculation: The doctor can do b timeout measurement of the double parietal diameter of the fetal head, the length of the head and hips and the length of the femur can estimate the gestational age, and calculate the expected date of birth.

Since it is difficult for every pregnant woman to accurately determine the time of conception, it is medically prescribed that the expected date of delivery is calculated from the first day of the last menstrual period, and the entire pregnancy period is 280 days, 10 gestation months (each gestation month is 28 days). The calculation method is calculated based on the first day of the last menstrual period, subtracting 3 or adding 9 to the month, and adding 7 to the number of days. For example, the first day of the last menstrual period is April 21, 2000 in the solar calendar, and the expected date of delivery should be January 28, 2001.

If you only remember the first day of your last menstrual period on the lunar calendar, you should convert it to the solar calendar and then calculate the expected date of delivery. It is important to note that the actual date of delivery and the estimated expected date of delivery can differ by 1 to 2 weeks. If you can't remember the date of your last menstrual period, you can ask your doctor to estimate it based on when the first trimester reaction began, when the fetal movement began, the height of the uterine fundus by hand, and the length of the uterus by measuring the length of the uterus.

1. Menstrual inverse algorithm.

Based on 280 days (40 weeks), add 9 (or minus 3) to the month on the day of the last menstrual period, and add 7 to the date. For example, if the date of the last menstrual period is January 15, then 1 plus 9 equals 10, 15 plus 7 equals 22, and the due date is October 22.

This inverse algorithm is based on a 28-day menstrual cycle, so it must be corrected for the length of the individual's menstrual cycle.

2. Pregnancy calendar algorithm.

Using a commercially available pregnancy calendar in the form of a simple or disc, the number of weeks of pregnancy and the expected date of delivery can be calculated by comparing the date of the last menstrual period. This method and the inverse menstrual algorithm may differ by day.

If you are unclear about the date of your last menstrual period after pregnancy, or if your menstrual period is not very regular every month, you can estimate the expected date of delivery by ultrasound. Extrapolation based on the results of ultrasound is usually accurate. Generally, through B-ultrasound examination, the length of the embryo can be specifically understood, and the doctor will calculate the expected date of delivery according to the B-ultrasound list, and use the B-ultrasound method to estimate the expected date of delivery, which is more accurate than the expected date calculated by the date.