Yeah they do get bigger i had under muscle im 5 wjs post op and i can see changes every week with mine.. Mine r still quite hard so have loads of dropping and fluffing to do still. Im not seeing nurse until 7 wks as i couldnt get time off work. But ueah apparantly once the muscle heals the implant relaxes and then you see results as muscle is holding it in place atm.. Hope that makes sense lol xx