mirena after 5 years

Hey guys !
Questions for fellow mirena users. Saw my GYN last month thinking she would put in a new IUD as mine was a little over five years old and she said its fine to leave the old one in. She said although hormones might be diminishing the device itself would still physically block from pregnancy, but I might heavier periods or irregular bleeding. Anyone else have experience with an older mirena. Did have side effects ? Hubby and I want babies but weren't planning to try until next year.
thanks !!