BFP=big fat positive
BFN=big fat negative
In regards to being pregnant or not
AFM=as for me
Tww=the dreaded two week wait between transfer and blood test
PUPO=pregnant until proven otherwise in the tww
EPU=egg pick up
DP=days post (When talking about being so many days past something) eg:3dpo=3 days post ovulation, 3dp5dt=3 days post 5 day embryo transfer.
Those are the main ones in the IVF forums, there's a big list somewhere on bub hub but I've never been able to find it. I just nod and agree at most of them, lol.