You can use any size that you’re comfortable with using. Cup companies only use age and pregnancies as a guide but if a small isn’t sufficient for your flow, then a larger size would be a better option.
There are also some high-capacity cups that the small hold close to or more capacity than the average cup (15-25 ml).
Check out the Tieut, Venus Cup, LaliCup, Super Jennie, Merula, MyCup. Some of these brands offer three different sizes.
Good Luck! <3
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