How many days after a delayed period can you test to see if you are pregnant?

Patient's question:

Main symptoms: Delayed menstruation
Onset time: Test results: Treatment history and effectiveness:
September 28th was the last time I had my period. On the first day after my period ended, I had sex with my boyfriend! But I’ve been waiting for my next period. Now, it’s November 2nd, and it’s been eight days since it was supposed to come, and it still hasn’t arrived. I’ve taken pregnancy tests three times...

Doctor's answer:

If menstruation is one week early or late, it is a normal phenomenon. First, it is necessary to determine if pregnancy is the cause. If menstruation is delayed, factors such as stress, dietary changes, work pressure, environmental changes, and gynecological diseases may all contribute to the delay.
After a 7-day delay in the menstrual cycle, an early pregnancy test can be used. If two red lines appear on the test paper, it indicates a positive result, meaning pregnancy.
To test with an early pregnancy test, use morning urine and check the results after 15 minutes. If there is one red line, it means pregnancy is not present. If there are two red lines of the same color depth, it indicates pregnancy. If the lines are one deep and one faint, it suggests the possibility of pregnancy, and you should test again after 2 days until you get either one red line or two lines of the same color depth.
It is recommended to consult a doctor for a pregnancy test to confirm the result if necessary.