If the urine test is one bar 30 days after intercourse, it generally means negative, but it does not accurately rule out pregnancy because the test paper detects a urine pregnancy test and there may be small deviations. It is recommended to wait patiently for the next period or to have a blood hCG test for confirmation. Since each woman’s menstrual cycle is different and ovulation occurs at different times, a detailed medical history is required. If you test negative for urine hCG after 30 days of intercourse, you may need to wait another 1 week for a second test to determine if you are pregnant if you do not have a period, or you can go to the hospital to test by blood draw. Because urine hCG is a semi-quantitative test, it will be positive only after a certain threshold, and if a particularly small amount of hCG is present, the test paper of the urine pregnancy test will not detect it. However, the blood test is more sensitive and is a quantitative test. The quantitative immunoassay for blood hCG in non-pregnant women is <3.1 μg/L, and when the blood concentration is >25 U/L it is positive for pregnancy. Therefore, it is necessary to make a judgment based on the condition, clinical manifestations, and menstrual cycle, combined with the results of the test, and it is not possible to judge whether a urine test with one bar after 30 days of intercourse is accurate or not from the test alone. Some women simply think that they are not pregnant because of the presence of one bar in the test, and take a series of oral medications. When they test positive for hCG and consider being pregnant, they worry whether taking the medication will affect the fetus. Therefore, in daily life, if you test one bar with a test paper, you should not take it lightly and retest after 1 week, or if you are more anxious, you can take a blood test for hCG to determine if you are pregnant.