If the patient is not pregnant, the normal range of HCG is 0-10mIU/mL. If the patient’s blood HCG test is less than 0.5mIU/mL, it proves that the patient is not pregnant. However, patients need to refer to the test time to determine the accuracy of HCG test. If the patient has had intercourse for more than one week after ovulation is confirmed, or if the last intercourse has been more than 10 days after ovulation is not confirmed, then a blood HCG test of less than 0.5mIU/mL will be able to determine with great certainty that the patient is not pregnant. If the patient’s HCG test is performed within a week of the last intercourse after ovulation is confirmed, or within 10 days of the last intercourse without confirmed ovulation, the result may be a false negative, that is, the patient is pregnant but not detected. This is mainly because it takes one week for the sperm and egg to meet to form a fertilized egg and to settle down.