ICSI advice

Hi!

My husband and I have been trying to conceive for a while. We found out her has very low sperm count, the only found 2 sperm in his first sample. We did a PESA and TESA and they were only able to extract one sperm. They froze the one and told us he could bring in another sample for semen analysis and they would freeze any sperm that were there and we could continue to do this. Does anyone know how many sperm you ideally want frozen before doing ivf? Anyone had an experience with sperm count this low? We are pretty discouraged and would love to hear any advice you have!

Thank you.