The expected date of delivery is July 30, and the last menstrual period is presumed to be October 23 of the previous year, and the time of conception is the ovulation period after the last menstrual period. Currently the main method used to calculate the expected date of delivery is the last menstrual period projection method, according to the pregnant woman’s menstrual cycle is a regular 28 days, and the 14th day is the day of ovulation to estimate, the pregnancy period is 40 weeks, that is, 280 days, through the calculation of the expected date of delivery is July 30, the last menstrual period is the previous year on October 23rd. For the calculation of the due date, it is based on the first day of the last menstrual period, the month minus 3 or plus 9, and the date plus 7. The week of pregnancy is usually rechecked at mid-pregnancy based on the early pregnancy ultrasound, and the patient’s menstrual period. If there is a big difference between the estimated date of labor after checking and the projected date of labor, the ultrasound should be used to check the week of pregnancy. During pregnancy, pay attention to rest, and should relax, avoid tension, anxiety, any discomfort should be timely to the hospital, the doctor for a clear diagnosis, and cooperate with the doctor to deal with the symptoms.