Most women will comfortably wear both cup sizes.
There is not a big difference between the two sizes the recommendations are based on what fits most women and to prevent leakage. The large cup (Size 2) is recommended for over 30 even if you have not given birth because as we age our hips will widen and the vaginal muscles lose elasticity.
Because women come in all shapes and sizes there are another couple of factors (blood flow, cervix height, general physique) you may want to consider before purchasing. If you are still unsure you may want to purchase the starter kit which contains both sizes.
With a lower cervix you may be better with the shorter size Small (Size 1).
Each woman's cervix is positioned differently and will also change position throughout during her period. For some, the cervix descends low into the vaginal canal while for others it sits high. If your cervix is positioned at a low to medium height in your vagina, CleoCup Small (Size 1) will work great for you. If your cervix is at a medium to high location, you can choose either size CleoCup.
So how the heck do you find out what height your cervix is?? You can use a clean finger to get an idea of where it sits shown in the diagram below. It is safe to say if you can't feel it even if you have little fingers it high.
Some women will go up to a Large (Size 2) if they have a heavier flow.
How your CleoCup fits inside you will be unique to your body. Your own individual shape, pelvic muscle strength, and vaginal condition can determine which cup works better for you. Active women, whose pelvic floor muscles are strong, are better suited for CleoCup Small (Size 1) while women whose pelvic floor muscles are not as strong might benefit from using CleoCup Large (Size 2).
If you are still unsure send us an email at firstname.lastname@example.org.
We also recommend the CleoCup Starter Kit which has both sizes in it so you can try them in the comforts of your own home and see what you like the most.