How long after an abortion would it be safe to use tampons again?

2 weeks. For an uncomplicated procedure, 2 weeks is enough time for the cervix to return to normal & for any additional problems to arise (retained tissue, clots, infection). Tampons & intercourse are usually ok by then & of course a reliable birth control method. Use condoms until your doc recommends what's best for you.
Abortion/tampons. Generally noting should be placed in the vagina for up to a week following an abortion. If you are still bleeding - use pads. After about a week you should be safe to use tampons - just change them frequently and if you start to notice an odor or run a fever call your doctor immediately.