Changes in areola??

So a friend of mine is pregnant she said her areola color changed darker and that's what she noticed making her think she was pregnant so for all the moms and mommies to be out there is this something you noticed and how far along were you when u noticed that change?? Just wondering because I didn't pay attention during first pregnancy (i wasn't TTC then) but I ended up having a miscarriage at 8 weeks so maybe it was to early for that to change or I was just worried about my baby. I'm TTC now but I've noticed no change as of yet still waiting out this TWW!