In clinical practice, the method used to find out if you are pregnant through blood tests is to draw blood to check for HCG, and if the result is greater than 10 mIU/mL, it indicates that you may be pregnant. It is advisable to have the blood test done after 31-32 days of menopause for a higher chance of a positive result. If the result of the first blood test is negative, and after 5 days there is still no menstruation, it is recommended to go for another blood test 2 days later. This is because sometimes the menstrual cycle may be delayed due to environmental or emotional influences, and ovulation may be delayed as well. In this case, the pregnancy test will be delayed, so it is recommended to take another test. If the result of the re-test is still no pregnancy, clinically it is possible that there is no pregnancy, it is recommended to take oral progesterone to promote menstruation.