Half Fertilised Egg Divided IVF

We've started our first cycle of IVF. Egg collection was Wednesday just gone. They retrieved 11 eggs. Only 5 matured and only 1 fertilised normally. Unfortunately this failed to divide.

There was another one that fertilised abnormally so couldn't be used. There was also one that they were monitoring as it was half fertilised and they were hoping that it would still work. 

They called me first thing yesterday morning to let me know about the normally fertilised one failing and to tell me that the half fertilised one had actually started to divide however, they didn't know 100% that it actually fertilised as they didn't see it happen. I had this one transferred. I've literally seen nobody else have this happen and was just wondering if anyone else had maybe been through it. They've warned us our chances of success are low, but possible. So not feeling very hopeful.