I found that most do it round 3 or 4 weeks pregnant, both my pregnancy's I had to wait til I was 3 weeks to do a test. I found Clear Blue brand to be very reliable, and 3 weeks is the minimum they work.

Most tests ive heard of can detect pregnancy one week after conception,just read the packets  or ask your pharmacist,hope this helps,goodluck

If you believe you're arleady 3 weeks pregnant, I am assuming that you've already missed a period. If this is so, then you can pretty much use any pregnancy test and be able to trust the result.

Hi there,

There are early pregnancy tests available, a few that will be able to tell you if you are pregnant by 3 weeks. First response is a brand that comes to mind, i am pretty sure you can test as early as 5 days after conception.

most  tests will show you yay or nay now it may only be faint test again in a week. but if you want to be doubly sure go to doc and he'll do blood test..good luck with the wedding and all!

there is some tests that can detect that you are pregnant within 24 hours of falling.