Oh, believe me, I check the expiration dates. No way would I mess with that. The extra packs I had were when my ex-gyno was changing my pills. I had 2 packs of diff. kinds of pills that she had switched me from. She changed my pills like 3 times thinking that they had something to do w/my bleeding THEN she had given me the depo-provera shot....and I think that lasts for 3 or 4 months.
When my new gyno took out my fibroid, I went back on the pills I had never truly had a problem with in the first place.
My wife was on depo provera when she got pregnant with no. 4. The stuff is supposed be 99 percent effective. We were stunned, as were the medical folks. In some cases, you cannot get pregnant for up to a year after you stop taking the shot. Upjohn tracked her for a while, because she is a statistical anomaly.
Even though no. 4 was a surprise, I wouldn't trade her for anything. She's an angel.