If i get pregnant on the mirena (levonorgestrel) will it hurt the baby?

Probably not: It is best, however, in that infrequent situation to have the device removed, if that canbe done easily--primarily to reduce the risk of miscarriage.

Probably not: If you get pregnant with an iud, it is best to remove it asap. Bare in mind the attempt at removal could in itself cause a miscarriage, but it is best to try to remove it if the strings are visible.