I had my embryo transfer on 11/29/2012 i took i pregnancy test on the 12/1/2012 it was positive and another on 12/4/2012 that was a negative why?

Trigger shot gave +: The first pregnancy test you took was too soon after the embryo transfer - it was probably positive from the HCG 'trigger shot' that you took before your egg retrieval (hcg is pregnancy hormone). The second test on 12/4 is too soon after transfer to get a positive. If you had a blastocyst transfer you should wait 9 days post transfer before taking a pregnancy test. Talk to your clinic. Best wishes.

False positive: It is too early to check a pregnancy test so soon after an embryo transfer. Typically pregnancy test can be done 2 weeks after egg retrieval or 11 days after day 5 transfer. This may have been a false positive. Good luck.