Confused about Pre-cum?

So I am sort of confused about what pre-cum is and if it can get you pregnant. My boyfriend doesn't ever have pre-cum, or at least it's very little. We had unprotected sex the other day, he came earlier that day, but peed at least 4 times before we had sex. He didn't cum in me. (We both decided to use condoms from now on) but what are the chances of pregnancy? Does peeing kill of the sperm, if any? I'm just curious, thanks!