This question is from 2008.
Yes you can, especially since he is putting it back in after he ejaculates.
Yes you can get pregnant by this method. You really should search online regarding safe sex so that there are no "oopsie's".....
The possibility is there, as he'll have some semen on the tip of his penis, and will also have some leftover semen inside his penis that usually seeps out some time after he cums.