Which size?

The Mooncup and MCUK are available in two sizes:‘A’ and ‘B’. Size A measures 46mm in diameter and 50mm in length. Size B measures 43 mm in diameter and 50mm in length. Both sizes have a pull stem 21mm long, which you can trim to the length that is right for you.

Sizing is based on pelvic floor tone, not menstrual flow, and it’s important to get the sizing right to get the best from your Mooncup or MCUK. Pelvic floor tone will vary according to your age, childbearing history and what sort of exercise you do. Corrective surgery to the vagina will also have implications. Check the guidelines to see which size you need:

Size Table

Size Size A

Because vaginal and pelvic floor tones naturally reduce with age, the size ‘A’ is recommended for women aged 30 or over. The difference between the ‘A’ and the ‘B’ is only small (3mm), but it is crucial!

Size ‘A’ is also recommended for all women who have given birth vaginally, regardless of age.

Size Size A

Designed for young girls and women under the age of 30 who have not given birth vaginally. It may also be suitable for women over the age of 30 who have had corrective surgery to the vagina, or who are advanced in tone-maintaining activities such as yoga, dance or pilates.

If you’re unsure of what size you need, please contact our Advice Team

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My period always used to be a complete drama, cramps, leaks, discomfort and tampons and pads were disgusting and uncomfortable. Also, I do dancing and swimming so it was always very awkward to do these things at my time of the month. I was desperately looking for an alternative. Thank goodness I found the mooncup! I was excited and nervous for using it because being 14, I still have my hymen intact and I thought the mooncup would hurt. Initially I was right, insertion was painful and frustrating so I emailed the mooncup team- who were extremely helpful- and with some practice it was dead easy! I recently went on holiday to France and I was due on, my first time with the mooncup- no cramps, leaks or paranoia. I even forgot I was on! Whenever I emptied the cup it was never even half full- even on my heaviest days, and I didn't feel it. As for dance and swimming, my period isn't even a problem with the mooncup. I haven't changed it in a public toilet yet but I don't feel the need to, seeing as it lasts so much longer so I can just empty it when I get home from school. Yes, at first I thought it's be disgusting but really it's just as much contact with blood as with a tampon or a pad. If you are like me, a teenage girl and you are sceptical about using the mooncup, just try it, honestly, after some practice it gets so much easier and periods aren't a worry anymore. It's eco-friendly, comfortable, money efficient, reusable, easy to use, so what have you got to lose by trying it? Thank you so much for improving my period, mooncup!
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How to use the Mooncup

Made in the UK

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Buy a Mooncup online or find your nearest stockist

Mooncup is available at Boots and independent shops everywhere