The inner cells of the hymen are the same type of cells as the vagina so it is sensitive to the hormone estrogen. When a girl enters puberty her body begins to produce estrogen. The hymen will thicken and become more elastic. It will often change shape to a ring or annular shape to form a ring or part of a ring around the vagina’s opening. This change from thin and inflexible to thick and elastic happens to the degree where it will not even be possible for a doctor to determine whether she uses tampons or not by examining a hymen. This thickening can happen right at the start of puberty or at the end, or anywhere in-between. This change determines the amount of discomfort she will experience at first sexual intercourse from the stress on her hymen. Before this change, every time something is inserted into the Vagina (finger, vibrator, dildo or tampon), the hymen risks being torn and stretched. Any hard landing, hard bump to the genitals or hard bounce to a girl’s body can also break the hymen. Sports like dancing, gymnastics, cheer leading, horse back riding, mountain biking, skiing and many others are implicated in the premature disappearance of the hymen. Going down a water slide feet first, jumping into a pool feel first and water skiing can force water into the vaginal entrance and damage the hymen. You can think of the hymen as a wine glass in a box with cotton balls. The cotton balls and the box will absorb some knocks and bumps. At some stage however if you bump it hard enough, the glass will break. The first time a woman has intercourse, the hymen will be stretched or torn and start to wear away. The vaginal opening will soon have nothing left of the hymen but hymenal tags (carunculae mytriformes) and is called “parous introitus”. This process will culminate with natural vaginal child birth after which no part of the hymen will be left. A small ridge can then be felt where the hymen were, but that will be all that is left.