We have been trying but....

So my husband and I have been trying for 16 mos now with no luck. Neither of us have been to the dr yet to see what is wrong.And i am on time every month with AF and ovulating.. I know for fact he will give a sample but there is one thing in the back of my mind that makes me wonder... so here's the story. My husband was in an awful car wreck when he was 17. He basically died on the table and was brought back. I am not sure if anyone has experienced this....but my question would be...with him being brought back, would that affect him by making him sterile? I know that is a silly question. I just want to throw that out there. Please if anyone has any input, i would greatly appreciate it:)