6 Top Reasons Why Your Menstrual Cup Leaks

Menstrual cups that fit well make life so much easier! It is super aggravating when they don’t though. You want to be able to rely on your menstrual cup and not worry about leaks.

We assembled the top 6 reasons why your menstrual cup may be leaking below

#1 The Diameter is Insufficient to Make a Seal

More than any other reason, diameter seems to be the main culprit in why a cup is not making a seal and leaking.

Even if your flow is very low, adequate diameter is necessary to make a sufficient seal.

Here at MeLuna we have 4 different diameters so it's easy to go up just one size. Here are the dimensions of the MeLuna menstrual cups:

all meluna menstrual cup dimensions and volume

Are you coming to MeLuna from another menstrual cup brand like Diva, Lena, Lunette, Saalt, Flex, etc.? 

We have created some side by side visuals to see what the next diameter up would be in MeLuna

Here's a quick glimpse of cup diameters:

Menstrual Cup Diameter Comparison

If you currently have a cup from another brand that is leaking, check out our page on switching brands to get access to more side by side comparisons on different menstrual cup brands here:

Switching Menstrual Cup Brands

Guidelines for selecting menstrual cup size

We found the following guidelines to work well for most users



What’s the Fix?

Be sure to purchase a menstrual cup with adequate diameter. If you purchase a menstrual cup from MeLuna USA that turned out to be not a great fit, check out the MeLuna USA Guarantee to help you get your Goldilocks!

#2 Height is incorrect for Your Body

Did you feel intimidated by using a cup and decided on the smallest cup possible to start out with? Shorty cups are great for users with unusually low cervix. These users generally simply can’t wear the standard length cups and shorties are their best and only option. If however your cervix is of average height or higher, a shorty cup can be prone to tipping over and leaking.

Do not order a MeLuna Shorty if do not have a low cervix.
Would you like to learn more about menstrual cups for short cervix? Check out our page Menstrual Cups Perfect for Low Cervix

What’s the Fix?

Be sure to purchase a menstrual cup with adequate height. Check out the MeLuna USA Guarantee to help you get your Goldilocks if your first MeLuna was not perfect for you

#3 Your cup is too Soft for Your Activity Level

If you purchased an extra soft cup or simply have too much core engagement in your activities for a regular firmness menstrual cup, your cup could leak because of compression.

Please note though: Not all sports or activities require a firm cup. Your cup is at risk of getting compressed if you have to engage your core substantially.

woman working out during her period

What’s the Fix?

When selecting a new menstrual cup it is tempting to go with the softest one possible (often called ‘sensitive’ by other brands). 

Unfortunately many users find the super soft cups are difficult to use in regards to keeping a seal. For most users -even very active ones- the Classic MeLuna is of adequate firmness. If however your activities require a firmer cup, don’t be afraid to try a MeLuna Sport!

Some cup users enjoy having more than one cup to get the perfect fit for different situations. Check out our blog post on multiple cups here.

Would you like to learn more about menstrual cups for sport and exercise?
Check out our page Menstrual Cups for Sport and Exercise.

#4 Your Menstrual Cup is not unfolding

Depending on size or insertion technique, it’s possible that your cup is not fully unfolding and staying collapsed in a C-Shape.

IMPORTANT: Staying collapsed is NOT the same as taking on an oval shape. For TPE cups taking on an oval shape is normal and desirable and does not lead to leaking,

To read more about why TPE cups turn oval check out our FAQ page!

What’s the Fix?

Your first step should always be to try a folding technique more suitable to have your menstrual cup pop open. Check out folding techniques on our page: How to Insert Your Menstrual Cup.

The Punch Down Fold tends to be a great one to use. Twist the cup a little bit to see if it will pop open. 

You can also try this when inserting your cup: Push it a little higher than needed and then gently pull it back down to let it settle into place. This generally opens the cup and creates a good seal for most users.

If none of this helps you have two more options: Purchase a cup with a diameter one size down or purchase a cup in a firmer material. If you purchased your original cup from MeLuna you can make use of the MeLuna USA Guarantee to get your Goldilocks!

#5 Your Menstrual Cup is not inserted correctly

Unfortunately the cervix is not necessarily located at the very end of your vagina. It’s more off to the side in many cases. Cervix position also changes throughout your period and it’s very common for it to sit lower during the first few days and higher during the last few days of your period.

menstrual cup inserted wrong

Depending on anatomy it is possible to bypass your cervix

When menstrual fluid is expelled from your uterus it exits from your cervix. If you place your cup too high, past your cervix, the fluid can’t be collected in the cup and simply by passes the cup.



What’s the Fix?

This one is easy, free and fast! If there is a chance you bypassed the cervix your first step will be to locate it. You will need to use your fingers to feel for it. Your cervix will feel like a bump coming down inside your vagina, kind of similar in feel to a nose. Once you feel it be sure to place the opening of the cup right underneath rather than above.

A Few More Thoughts on Menstrual Cup Placement:

How can cup position be adjusted to accommodate a sensitive cervix and prevent discomfort or cramping?
To prevent discomfort or cramping from a sensitive cervix, it is recommended to experiment with different cup positions until you find the right one for your body. Avoid positioning the cup directly on the cervix and consider placing it underneath rather than above the cervix to prevent discomfort and ensure proper fluid collection.

What potential issues can arise from positioning the cup directly on the cervix, and how can they be avoided?
Placing the cup directly on the cervix can lead to capacity issues and raise the level of fluid inside, potentially causing leaks. Moreover, for individuals with a sensitive cervix, the cup's suction could trigger cramping or discomfort. It is advised to try out different cup positions to find the most comfortable and effective one for your body.

How can estrogen levels during the period impact the cervix and cup placement?
Estrogen levels during menstruation cause the cervix to lower and become firmer, which can influence the position of the cup. This may affect how the cup interacts with the cervix and the fluid inside, potentially leading to leaks if not positioned correctly.

What is the angle of the vaginal canal and how should the cup be angled for correct positioning?
The vaginal canal is angled towards the back of the body, not vertical. To ensure correct cup positioning, it is advised to angle the cup towards the tailbone using your thumb on its base to tilt it in the right direction.

How does the cervix's position change throughout the menstrual cycle and how does it affect cup placement?
Estrogen levels during the period cause the cervix to lower and become more firm, which can impact the position of the cup. It's recommended to check the cervix's position throughout the cycle as it may continue to move, affecting where the cup needs to be placed.

#6 Your Flow requires more frequent Emptying due to Cup Volume

All menstrual cups will leak once they reach capacity. Shorty cups will have less capacity than standard cups because of the reduced height.

If your flow is heavy but due to low cervix you require a MeLuna Shorty cup for low cervix, you may have to compensate for the reduced volume by emptying the cup more frequently.

volume of a menstrual cup affects capacity



What’s the Fix?

If your low cervix makes it necessary to wear a shorter cup it will impact capacity. It may be normal for you to empty your cup more frequently.

Get answers from the Menstrual Cup Quiz

If you have a cup that's not working well for you and are curious what cup may fit you better (without leaks!) check out the Menstrual Cup Quiz!


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