I also got a high number at epu (14) with 8 fertilise.
Scientists look at embryos 1st day to check for fertilisation and let us know, leave them alone until day 3 (give us an update IE. "Your embryos are doing well and your on track for transfer" then leave them alone again until transfer day.
In my case of my 8 fertilized I was told on transfer day that there were none to freeze and the 1 little fighter was 'a bit slow' although was transferred on Sunday and I am currently in the 2ww with all my hopes pinned on this little fighter!! We were shocked and devastated to say the least! Last stim we got 7 out of 7 eggs fertilized with 2 grade A blasts on day 5 - 1 transferred & 1 frozen (what went wrong this time?! who knows?) as MTC reminded me like I remind everyone else 'it only takes 1!' xx