There is no right or wrong when it comes to choosing a cup. Most people can use both sizes, small for lighter days and regular for heavier days. But usually, one tends to fits just that little bit better than the other.
how to measure your cervix
With clean hands, insert one or two fingers into your vaginal canal. Feel for the opening of your cervix. This should feel similar to the tip of your nose with a tiny hole in the center. If you can reach your cervix with your finger inserted to the first knuckle you have a low cervix. Second knuckle, medium cervix and third knuckle high cervix.
If your cervix height is low to medium, we recommend you choose the yoni small. If your cervix height is medium to high, we recommend you choose the yoni regular.
Your cervix can change position throughout your cycle. Your cervix may descend lower into the vaginal canal or continue to sit higher during your period, it's best to check your cervix height once your period starts.