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Silicone or rubber menstrual cups are reusable, flexible, bell-shaped devices that collect your menstrual flow. The cup should not leak if inserted properly and is one of the best alternatives to a tampon if you want to go swimming. Insert the cup before swimming, and leave it in until you can change out of your swimsuit into your regular clothing and switch to another method of period protection. While they can be expensive compared to tampons or reusable cups, disposable menstrual cups are flexible, easy to insert, and work well for protection while swimming. Just as you would with a reusable cup, insert the cup before swimming, and leave it in until you can change out of your swimsuit into your regular clothing and switch to another method of period protection.  Like reusable cups, disposable cups can be messy to insert and remove and require a learning curve to master placing them correctly in the vagina. Check out  this helpful wikiHow page to learn the process of inserting and removing a disposable menstrual cup. If you avoid tampons because you are concerned about the chemicals used in their production, a natural sea sponge might be a good solution for you. Sea sponge tampons are harvested from the ocean and contain no chemicals, and they are also reusable.

Summary:
Try a reusable menstrual cup. Consider a disposable menstrual cup. Consider a sea sponge.