The pregnancy cycle is not counted from the time of menopause, but usually from the first day of the last normal menstruation, if you are not sure about the last menstruation, you can also project through the ultrasound in early pregnancy.
The pregnancy cycle is usually calculated from the first day of the last menstrual period, pregnant women in the month of their menstrual period plus nine or minus three is the month of the expected date of delivery, the number of days directly plus seven is the expected date of delivery day, the general pregnancy week is 40 weeks.
For pregnant women whose menstrual cycle is not accurate and who are not sure about their last menstrual period, they can also use the results of ultrasound examination in early pregnancy to project, which is a relatively accurate algorithm.
Accurate calculation of the pregnancy cycle, you can project the expected date of delivery in advance, but also according to the pregnancy week to determine whether the development of the fetus is normal.