Thank you.
I just wanted to say thank you to everyone who took the time to reply to my message.
You are right. I am looking for an answer and like you say there is never going to be any definite answer. How much easier it would make things though, just to know why so that it can be prevented next time.
I am very lucky having a wonderful family already, and I really feel for those who don't even have that. We are lucky in the fact that we have 6 frozen and can try with those. I know how difficult it is for some of my friends that have had to go through the whole cycle every time, sometimes not even ending up with anything.
Again, thank you!!