I was worry about this for a couple of days. About a some months ago, my boyfriend and I where messing around...he was fingering me and I was giving him a hand job. He always likes it when I let him rub his erect penis on my vaginal area. We did this for about ten minutes. He did put it in for about 20-30 seconds at one time. I am just worrying about the chances of being pregnant. What are the chances from precum? Well, now I know the answer.