Hi u/Monkeypet \- Thanks for your post! Great questions... A) Indeed, more males stutter than females. The reasons for this probably have to do with the genetic factors underlying stuttering. Interestingly, close to onset, when children are very young, the sex ratio is more like 2:1 or 1:1... over time, many boys and girls recover, but girls recover at a higher rate, leading to the 3:1 or 4:1 M:F sex ratio in adults. Perhaps there are sex-linked aspects of the genetics or the neurological differences. B) Why do so many outgrow stuttering? That's one of the key questions that researchers are trying to understand right now. We know that there are high recovery rates for young children, but we don't know exactly why. It appears that there are differences in the brain between children who stutter and persist in stuttering, children who stutter and recover, and children who never stuttered. There are several excellent research centers where people are looking into this, including research being done by Dr. Bridget Walsh in my department here at Michigan State University, as well as work by Dr. Soo-Eun Chang at the University of Michigan. We have a lot to learn yet, but answers are coming!