Good luck on Sunday!! I am so excited you are finally getting to retrieval stage. You have been waiting for so long!!!
Not sure yet I have an u/s tomorrow and should know then...but they are thinking Sunday..
Trigger helps your follicles to mature. At the time of the trigger I only had 4-8 mature follicles but 15 mature eggs were retrieved. So, the trigger adds a really nice boost.
When are you triggering?
I think the trigger gives them the last boost they need so they continue to grow until they are retrieved. Thats what I have gathered from my RE and from all the reading I have done. Good Luck. I will be starting IVF next month :)
Jessica