I've lost mine to. Not wanting to/not being able to afford to pay £30 each to replace them I got my old secondary school to send me a letter confirming my results. This was fine when I started my PGCE. My first teaching post haven't asked to see them
I have just got a new job and was asked to show all my certificates, o level, a level, degree and PGCE. I did my o levels in 1986!!! I have been teaching since 1994. They took them all to photocopy and keep in my file, for safeguarding I think.