What are the chances?
 

Okay... the other night I had sex with my girlfriend. We began without using a condom, but I thought better of it and put one on. I also pulled out before ejaculation. She also is on the pill, however, she ran out a day or two after we had sex and hasn't refilled. Is this an issue? I know women need to stay on the pill for it to work. Maybe I'm just paranoid, but if anyone has advice, please let me know...

Well if she ran out of pills then she's at the end of her cycle and she should be starting her period now. Normally you don't start a new pack of pills until a week after you run out. Some pill packs have a week worth of placebo pills in the pack to take during that time. If she meant the real pills when she said that she ran out, then you should be ok. If she was talking about the placebo pills then you might have a problem. Your odds for pregnancy are probably pretty low, but don't do that again.

"pre-come" contains semen, and can make someone pregnant. So, there is a risk from fucking before you come without a condom. The quantity of semen is small, so the risk isn't extremely large. Do not make a habit of it.

As noted, the type of pill matters.

a day or two after sex your sperm have either already impregnated her or are dead, where do you think they are going to live? Vaginal Condos?

This has been answered but I'll do it agian, anything is possible, any sex without protection can = child(ren).

The odds are slim, but unless you like being called Daddy, don't take chances like that again.

I guess my question is: is the birth control ineffective if she only took one or two pills after sex?

Well semen only lives so long.
She ran out of birth control two days after you had sex.
I don't think the semen lived for two days.