How Do I Choose My Menstrual Cup Size? | LUÜNA

Menstrual Cup How-To

Thinking about starting your menstrual cup journey? Here's everything you need to know about choosing the best menstrual cup size.

Read more on cleaning, folding, inserting and removing your LUÜNA Menstrual Cup here.

Which Menstrual Cup Length Should I Choose?

When we're talking about menstrual cup sizes, the most important dimension is length, not diameter. Basically, a menstrual cup should sit completely inside your vagina - the cup stem shouldn't stick out beyond the entrance to your vagina. If it does, you may find it helpful to trim with scissors.

Trimming the LUÜNA Menstrual Cup

So how do you determine which menstrual cup length is the most suitable for you? It's all about the height of your cervix. Our cervix connects our vagina to the uterus and is totally unique to each person.

How Do I Measure the Height of My Cervix?

Although it may sound intimidating, measuring your cervix is super quick and easy. Whilst we always advocate seeking professional advice for any medical issues, this isn't really worth the trip to your gyno.  Measuring the height of your cervix can be done on your own and we should all feel comfortable exploring our bodies (safely) at home.

LUÜNA Menstrual Cup

Since our bodies fluctuate with our cycles, we suggest measuring your cervix height around the time you're menstruating. As always, the first rule is to wash your hands thoroughly. Then, slide your finger into your vagina (as if you were inserting a tampon) until you feel something a bit firm - similar to the touch to the tip of your nose. Good job: that's your cervix!

If you can only get one joint of your finger in before feeling the cervix, then you probably have a low sitting cervix. If you can get two joints, then you probably have an average sitting cervix. If you can fit the entire length of your fingers, then you probably have a high sitting cervix. Generally, a bigger menstrual cup size is better for those with a higher cervix & a smaller menstrual cup size is better for a lower cervix.

If you want to be really precise, with the tip of your finger still touching your cervix, place your thumb along your finger to mark all the length that fits inside. Keep the thumb in place as you remove your finger, and measure the distance to the tip of your finger with a ruler. Then you can easily compare that to the length of different menstrual cups!

Should I Consider My Flow When Choosing a Menstrual Cup Size?

Unlike pads or tampons, your flow doesn't really need to be taken into consideration when choosing a menstrual cup. Menstrual cups have a much larger capacity as opposed to tampons & pads. While those should be changed every 4-6 hours, menstrual cups can usually last you 12 hours (although some prefer rinsing them out more often).

Having trouble removing your menstrual cup? Read our panic-proof cup removal tutorial here.

We've also found that members of our community who have given birth vaginally may prefer the large menstrual cup, while others are more comfortable with the small menstrual cup.

LUÜNA Community with Menstrual Cup

If you need more help with the menstrual cup, we've got you! Feel free to reach out to our team of cup experts at

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