Wow ProudMumma34, that's depressing! Thanks for the info, but I'm choosing to be positive, I don't think it's productive for me to be thinking about worst case scenarios right now.
Thanks Heyside, we dtd the day before and the day after O (we think, it may have been the day of) but this time we will try every day around O and including O. My follicle was at 24mm before I had my trigger, I'm wondering if it was left a bit late. Last time my trigger was at 21mm. It was delayed this time because my scan was due on a Sunday before the public holiday. All I can do is keep trying and hoping!