How to calculate the due date if menstruation is irregular

How to calculate the due date if menstruation is irregular?

1. Calculate based on the first day of the last menstrual period. Generally, 280 days are counted from that day, and the expected date of delivery is the 280th day. However, for women with irregular menstrual cycles, it is impossible to calculate the expected date of delivery based on the first day of the last menstrual period. At this time, B-ultrasound can be used to observe the size of the gestational sac, the time when the fetal heart and fetal bud appear, and the top-buttock diameter to estimate the gestational age and thus determine the expected date of delivery. In this way, the error of calculation usually does not exceed 1 week.

2. In the early stages of pregnancy, we can roughly determine the number of weeks of pregnancy by testing the levels of HCG and progesterone in the blood. We can also estimate the number of days of pregnancy based on the date of intercourse and calculate the expected date of delivery. If the pregnant woman cannot remember the date of intercourse, she can roughly estimate the number of weeks of pregnancy based on the time of pregnancy reaction and fetal movement, but this may have a large error. If the pregnancy is achieved through assisted reproductive technology, the expected date of delivery can be calculated based on the date of the relevant operation.

3. The due date may be advanced or delayed. During pregnancy, you should have regular prenatal checkups. If the fetus is in good condition, you can wait for delivery with peace of mind. If there is still no effective uterine contraction after more than a week of the due date, you should go to the hospital for a check-up in time, and comprehensively evaluate the mother's condition according to the doctor's advice. If necessary, assist with intervention to deliver the baby as soon as possible to avoid affecting the fetus.