How early can pregnancy be detected through urine?

3-5 weeks after intercourse. It can be detected 7 days after intercourse with a blood test.

Answer

Actually, a home pregnancy test would be able to pick up a positive 2-3 weeks after intercourse, or up to 5 days before a missed period, or 4 days before you expect your period to arrive. Most women, however, will not receive a positive until after they have missed their period.