What to do if your menstrual cup leaks?

It can happen that you leak from your menstrual cup, and we know how unpleasant it is. These leaks almost always have a solution, but to find it, you have to identify the cause.

We have therefore listed all the causes we have identified, and for each one, their solution. 

But before you go on, you should know that when you start with a new menstrual cup, leaks are very common. That's why we recommend always lining it with an external protection for a while (among our other tips for beginners)

Don't be discouraged, it's normal and it will pass. Patience and perseverance will be your best assets.

And know that whatever happens, your menstrual cup is not too small for your vagina: it just can't be and that's not why you leak.

Cause 1: your menstrual cup is full

But it's often the first cause of leakage, so we had to mention it: as the cup is full, it will overflow. We know that if you're a seasoned cook, you can get overconfident from time to time and forget about your cup a little too long in relation to your flow.

It happens to all of us (but not for more than 8 hours at a time, we can't say it enough)

Often, those who have not yet taken the plunge ask themselves how they can feel when they have to empty their menstrual cup? Simply, you can feel the blood flowing out (like when you wear a towel) whereas with the cup, you should not feel anything!

The solution

Empty it more often 🙂 

Cause 2: The ring is not properly deployed.

A menstrual cup that doesn't expand, with a top ring that doesn't stick to the walls, is guaranteed to leak, simply because it lets blood through.

With traditional menstrual cups, the body of the cup must be expanded for the ring to expand. This is due to their conical shape and the forces acting on the material.

With La Cup Luneale , it is a little different, as it is not conical: its body can be flattened according to the tonicity of the perineum, the anatomy or the movements, even though the upper ring is well deployed.

The Solution

With a menstrual cup with a stem, the way to know if the ring is correctly deployed is often to go around the cup with your finger to check. Not necessarily practical, but effective.

With La Cup Luneale , you only need to turn it around about 1/4 of the way by holding it by the MoonPad (as if you were screwing it in towards the bottom of the vagina). As soon as it turns, you can be sure that the ring is properly deployed. That's all there is to it.

Cause 3: Your Cup is placed too high in the vagina (or your cervix is low)

Leakage is sometimes due to placement too high, in the fornix, or in any case after the cervix. 

Here is a diagram to help you understand: in the third case, the blood will flow next to the cup. Hence the leaks every time.

correct placement of the menstrual cup in the vagina


To find out if this case applies to you:

First step: try to position your cup as low as possible, about 1 phalanx away from the vaginal entrance. With a menstrual cup with a stem, you tend to put it high to 'get the stem in'. With La Cup Luneale , you won't have this problem.

Second step: are you still leaking with your cup positioned low? It is possible that you have a short vagina or a low (or even plunging) cervix (we will deal with this particular case later in the article).

In this case, we advise you to explore your body to locate your cervix. This is a small, spongy, doughnut-shaped lump:

  • If it is easily accessible, then your cervix is low. In this case, you will either have to cut the stem of your classic menstrual cup or use La Cup Luneale .
  • Or your cervix is really low, in which case you will need to choose a menstrual cup that is even shorter than the 5cm of La Cup Luneale (we hope to be able to offer a short Luneale cup one day!)
  • If your cervix is at a classic height, but your pelvic muscles or your movements cause the cup to move up towards the fornix (= case 3 on our diagram), then unfortunately we have no solution for you: it is possible that the menstrual cup is not a solution adapted to your body.

Finally, there is a special case: in the case of a retroverted uterus, there are some checks to be made which are the subject of a full article.

Cause 4: The holes in your cup are blocked.

If you feel 'air bubbles' at the same time as you leak, the holes in your menstrual cup are too small. This is the most common cause of leakage. This is often the case for those with thick to very thick periods.

This is because menstruation does not flow continuously: it is expelled by contractions of the vagina.

If you have a thick or clotted flow, the holes in your menstrual cup will become lined with this blood and clogged by the first influx. As your cup cannot inflate, the next influx of blood will start to pressurise it, as the air in it cannot escape through the holes.

So like a pressure cooker, after a while, plop, the air will suddenly come out of the top of the cup, taking blood with it (which has the texture of egg white).

The solutions:

  • Temporary solution (which works well if you have a weak flow): after inserting your cup, empty it of a little air by pinching the body slightly. If you have a classic menstrual cup (with stem), be careful not to deform the upper ring. If you have La Cup Luneale , don't worry, the ring will not move (see above)
  • Final solution for DIYers: Enlarge the holes of the menstrual cup. Do this gradually and very carefully. The holes in the Cup Luneale are 1.4mm in diameter and are calibrated for fluid to medium flow (as they can be enlarged, the reverse is impossible). So for example, you can start by making 2 of the 4 holes 1.6mm to 2mm. This should solve the problem.

How do I enlarge the holes in a menstrual cup? 

You can use a small pointed scissor, but this is reserved for those who are skilled. We tested it, it was not very conclusive...

If you have a plastic/TPE cup, you can use a heated needle, but this does not work with the silicone of La Cup Luneale . We have also read that you can do this with a heated needle, but what is valid for a plastic cup is not necessarily valid for the medical silicone of the Luneale cup (which is resistant to 240°C).

Ideally, you should invest in a set of cookie cutters that make precise holes from 1 to 5mm (plus, it will allow you to add holes to your belts etc.). You can also find scrapbooking pliers. The best results have been achieved with a tool, so it's a small investment, but if you don't have any leaks afterwards, it's worth it.


Cause n°5: the particular case of the plunging neck.

If you don't experience any leakage after you put on your menstrual cup, but it happens after a while and when you take it off it is only half full, you may be in this situation.

If you have a plunging collar, it may go down into the cup, sometimes quite far.

As a result, it decreases its capacity: your cup is "full" of your cervix + your period, but when you take it out, only your period remains. To detect this, simply pinch the body of your cup once it is in place, to feel whether or not your cervix is there.

The Solution:

Unfortunately, we don't have a miracle solution in this case, but we do have a clue: if you can estimate the diameter of your cervix, you can see whether it is relatively large or not. If it is large, the solution may seem strange: choose a menstrual cup with a smaller diameter. The cervix will then plunge less deeply into the cup, and therefore its blood content will be greater.

Obviously, this solution is only valid if your cervix is not thin. Because in this case, unfortunately, there is no solution: the menstrual cup is not adapted, or with a very small autonomy (which reduces part of the interest of the device)

Cause n°6: false leaks.

Let's finish with what may look like leakage but isn't: when you get tiny stains on your underwear, like streaks, right after you put on your menstrual cup.

When you put your cup on, the ring is the seal. However, blood can slip down the walls of the vagina between the time you take it out and the time you put it back in (especially at the peak of your period).

These blood flows are found after the ring, so they arrive at some point in your panties.

The Solution:

If you put your cup on in the shower, you can simply run a little water with your finger over the walls of the vagina that are under the ring.

And if you put it in the toilet, wipe around the bottom of your menstrual cup with paper or a Wipe Luneale.


Have you found the cause of your leaks? Do you have any other tips or questions? If so, leave us a comment!

Tips Cup Leaks

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