Going to try anal.

I want to try anal. And so does my bf. He has stuck a finger up there previously. I have read up on the topic and know to wear a condom(which I would never not let him). Use lots of lube, and be relaxed. However, is there any chance of pregnancy although he will be pulling out prior to cumming, wearing a condom, and it being anal? Any chance? And additionally, any advice? Thanks in advance