Yes, getting a perm with big rods could change your curl pattern. Perms are much more gentle than they have been, say in the 80's, but they are still tricky. Have your stylist do a hair analysis on your hair prior to the perm. This will help your stylist choose the right perm for you. If you have bleach in your hair, henna or hard water, you may not be a candidate for a perm. If you end up getting a perm make sure you have a good deep treatment plan to follow.