How late can the menstrual period be before pregnancy can be detected?

Patient's question:

No

Doctor's answer:

You can use a pregnancy test kit to detect pregnancy around 7-10 days after a missed period, or you can go to the hospital for an ultrasound or blood test to more accurately determine if you are pregnant. Sometimes urine tests can also have some errors, so you can currently have a blood test to check HCG to confirm if you are pregnant.