A pregnancy test, or pregnancy test, is a tool to check if a woman is pregnant. A pregnancy test with a single bar but with a red halo next to it may be pregnant, but the pregnancy is still relatively short caused by. A pregnancy test can determine if you are pregnant by detecting human chorionic gonadotropin (hcg) in human urine. When the pregnancy test has a bar, but there is a red halo next to it, it is possible that you are pregnant. However, the pregnancy period is still relatively short, and you need to take another test more than 7 days after the menstrual period is delayed. The test needs to be taken in the middle of the morning urine, pay attention to rest before the test, do not stay up all night. Pregnancy can only be confirmed when two red bars are detected on the pregnancy test stick. If you want to diagnose whether you are pregnant early, you can go to the hospital to check the blood hcg, specific discomfort, to go to the hospital obstetrics and gynecology clinic in time to check.