What Size Do I Need?

The question we get asked most has to be: “What size of Moon Cup should I buy?”. Many women have concerns about how their cup will fit, whether it will be too big or fall out, and whether a menstrual cup will fit their teenage daughter. Never fear, choosing the right size is actually quite simple!

The Moon Cup comes in two sizes, which are conveniently alphabetically coded:

  • Size “A” is for after vaginal childbirth
  • Size “B” is for before vaginal childbirth, or for women who have had C-sections when giving birth

It really is that simple for the vast majority of women interested in using a menstrual cup. Although we’re all slightly different shapes and sizes internally, almost all women will be able to use one of the two Moon Cup sizes because of the flexibility of the vaginal walls and the way most pelvis sizes are centered around two average measurements, corresponding to whether a woman has given birth vaginally or not.

Young or Petite Women
Many women interested in using a Moon Cup or purchasing one for their daughter(s) will ask us whether we offer a smaller size than the “B” cup. The answer is “no”, and here’s why: unless the young woman has not yet gone through a teenage growth spurt (perhaps she has only just begun to menstruate, at a younger age than average) and is still extremely petite, a smaller cup simply isn’t required. Because of the flexibility of the Moon Cup’s silicone material, it will conform to fit the vast majority of women.

Think about it: you don’t go out to buy extra-small tampons, you simply select the absorbency you require and expect them to fit your body. If your concern is more about learning to insert feminine hygiene products, it’s the same as with tampons. In fact, many of our customers have said that practicing with applicator-less tampons is very helpful in terms of learning how best to insert a menstrual product. If you’re thinking of purchasing a Moon Cup for your daughter, try getting her to practice with these first, in order to get comfortable with her body.

Vaginismus Sufferers
If you have vaginismus or another condition which makes insertion of anything painful or difficult, the Moon Cup may not be for you. If you are looking for other eco-friendly options, try reusable organic cotton pads which can be laundered. There are a number of companies producing these commercially, or you can search online for instructions to make your own.

If you have any other concerns or unique needs which might affect your use of a menstrual cup, try discussing your options with a gynecologist. We are also happy to answer any additional questions not covered by our FAQs. Feel free to contact us and we will respond as quickly as we can.