Thanks for your reply.I discussed with my doctor.My doctor said that 12 eggs were mature and resulted in embryos,but were very fragmented or did not grow.Thats why they had to discard those embryos it seems.
Going form 22 to 18 egg is not significantly different and the fact that you had 5 embryos vs 7 embryos confirm this. Your fertility can decrease with age but usually not significantly within a year. I think that you make enough eggs that you would not need to freeze them for the future. Did your IVF doctor discuss with you why you only had 5-7 good embryos despite so many eggs retrieved 18-22?