Reasons for failed fertilization during IVF?

Has anyone has been through

<a href="">IVF</a>

and had failed fertilization naturally (not ICSI) where the sperm did not penetrate the eggs at all. Did your Doctor explain what the cause was? We were unexplained but I think we may have a male factor issue that was missed. SO count is on the lower end but okay and apparently wasn’t an issue. ICSI was not advised. Maybe we have an egg issue too I’m not sure how that works? but my labs and amh were all good, had 25 eggs at retrieval and I’m 29, doctor sees no issue with me. I just can’t believe none fertilized at all.