Changes

Boys are born with a [[foreskin]] that is non-retractable for reasons of [[Immunological_and_protective_function_of_the_foreskin#The_protective_and_hygienic_function_of_the_foreskin| protection]]. The inner surface is fused with the [[glans penis]] by a [[synechia]] (similar to a fingernail that is glued to the nail bed of the finger). Also the tip of the foreskin is too narrow to retract. As a boy gets older, the synechia disintegrates and releases the foreskin and the foreskin gets wider as a boy ages, so the foreskin gradually becomes [[Retraction of the foreskin| retractable]]. A survey carried out in [[Denmark]] found that the mean age of first foreskin retraction is 10.4 years.<ref name="Thorvaldsen">{{REFjournal

Human [[skin]] can be stretched and normally returns to its normal size and position. But when stretching is done over a longer period of time, chances are that this stretching causes new [[skin]] cells to grow ([[mitosis]]) and [[tissue expansion]] to occur. We all know this from the [[skin]] which covers e.g. the human stomach or the breast area.