Holding Stem OPT for future purpose with H1B approved

Hello all,

Just a quick question about the stem opt. Well I was wondering if it is possible to hold our stem opt for future purpose with H1 being approved after initial opt? I know many people lose their stem opt once their h1b is approved after initial opt with out even using their stem opt. Is it really an option to hold their 2 years of stem opt in case if they are out of h1b visa or any other issues in general.