From what I have heard, breast growth is only a possible side effect. I am not sure if breast growth is more likely on one type of birth control than another, but I do know that not everyone's breasts get bigger. For those who do experience breast growth, I have heard that it is a minimal amount of growth and is temporary - after a couple of months they go back to normal.

I'm using ortho tricyclen lo and it made my boobs a little bit tender and bigger..But it's not that much...Just a little bit

I'm using ortho lo too and I can notice a slight change in the size, and i've only been on it for 5 months. Mine are not tender though, but everyone has different side effects...