03-02-2015, 05:43
Most likely it's glandular tissue growth, aka knots. When they don't hurt is a cause for concern. Or, another possiblity is what's called fibrocystic lumps.
http://www.mayoclinic.org/diseases-conditions/fibrocystic-breasts/basics/definition/CON-20034681
http://www.mayoclinic.org/diseases-conditions/fibrocystic-breasts/basics/definition/CON-20034681