Your hymen is a ring shaped piece of tissue just inside your vaginal opening. Sometimes the ring is complete and sometimes it is more like a horseshoe shape but either way, it is not a full membrane. It has a hole in the middle of it like any ring would. When you use a tampon or have sex or put anything else up there that’s a little bigger around than the ring itself it will stretch and may tear a little bit to accommodate what you are putting in. If the hole in the hymenal ring is bigger, a tampon may not stretch it enough to tear it at all. Some girls have already stretched or torn their hymen without even knowing it by landing right on their vagina on a monkey bar or the bar of a bike, so putting in a tampon won’t cause any discomfort anyway. If you are asking because you want to have sex for the first time without stretching and tearing it a little at that point and so you want to use a tampon to do the job ahead of time, I can’t guarantee it will work since it depends on how wide the hole in the ring of the hymen is to start with. When you are ready to have sex for the first time and have found the right person, you will be using a condom anyway so choose a lubricated one and have your partner enter you slowly and gently and that will ease any discomfort you have.
It is possible that your hymen will tear when you insert a tampon, but I wouldn't make that your mission. Unless there is an issue or problem with how your hymen is formed (which is pretty uncommon as far as I know), I personally think that your hymen breaking is one of those things just best left to nature.
You could probably do it, but there's really no need! Your hymen will break or stretch when it needs to. It might happen naturally the first time you use a tampon or insert anything else into your vagina. Mine broke when I was riding a bike!
