How the Menstrual Cup Should Sit (With Signs It’s Right)

“How do I know if my cup is in right?” If you’re asking yourself that right now, relax: it’s the most common question among people starting out with the menstrual cup, and the good news is that there are very clear signs that confirm it in under a minute. No guessing, and no spending the day with that uneasy “I’m not sure this is right” feeling.

If you haven’t inserted it for the first time yet, we recommend starting with our step-by-step guide to inserting the menstrual cup. Here we’ll focus on exactly what comes next: how to know, without a doubt, that your menstrual cup is properly placed.

The 5 signs your menstrual cup is properly placed

You don’t need any complicated tricks. Run through this mental checklist every time you insert the cup:

• You don’t feel it when you move. If you walk, sit down or climb stairs and don’t notice it, it’s in the right place. Medical-grade silicone certified to ISO 10993 is flexible and adapts to the vaginal walls without creating pressure when the seal is right.
• The stem barely shows. If you feel the stem rubbing or sticking out too much, the cup probably hasn’t settled all the way or the stem is longer than you need (you can trim it carefully once you’ve checked that the cup seals well).
• You feel the vacuum when you pinch the base. Gently press the base of the cup with two fingers: if you feel resistance, like a slight suction, the leak-proof seal has formed.
• It rotates smoothly, without pain. Once inserted, it should be able to turn 360° with no effort or discomfort. If it’s hard to turn or it hurts, it hasn’t fully opened.
• No leaking between changes. This is the real test: if you don’t stain your underwear in the first few hours after inserting it, the seal is working. The systematic review published in The Lancet Public Health (van Eijk et al., 2019, 43 studies and more than 3,300 participants) confirms that a properly placed menstrual cup has leakage rates equal to or lower than those of tampons and pads.

Where exactly the cup should sit inside the vaginal canal

Here’s the most common confusion: many people think the cup has to go “way up”, close to the cervix, like a tampon. It doesn’t. A properly placed menstrual cup sits in the lower part of the vaginal canal, several centimeters below the cervix, never pressed against it. It’s the cup itself, by opening and sealing against the walls, that collects the flow as it comes down — it doesn’t need to be “close” to anything to work.

If your cervix sits lower or higher than usual, the feeling of “where it should be” varies from person to person. That’s why it’s worth locating your cervix before choosing a size: it helps you understand why your cup sits deeper or shallower than your friend’s, and choose the right model. If you find out you have a high cervix, we have specific content on menstrual cups for a high cervix.

Common mistakes that stop the cup from sealing well

Almost all the leaks or discomfort you tell us about in private messages have the same origin: the cup hasn’t fully opened inside. These are the most common mistakes:

• Folding it badly when inserting. A poorly executed C-fold or U-fold can make the cup go in “squashed” and not recover its shape. Try different folds until you find the one that suits you best.
• Not rotating it after inserting. Turning the cup once it’s inside helps the rim open completely and removes any internal folds that let flow through.
• Pushing only the stem. The stem doesn’t seal anything; you need to make sure it’s the body of the cup that creates suction against the vaginal walls.
• The wrong size or model. A firmer body can be harder to open at first; one that’s too soft can collapse if your pelvic floor is tighter. Check the differences between the Sileu menstrual cup models to find the one with the best balance of firmness and comfort for you.

If you still notice leaks after checking all this, we have an article on the reasons leaks can happen with the menstrual cup, and another specifically on why the cup slips down if you notice it moving lower as the hours go by.

What if the cup is hard to take out after you’ve checked it’s in right?

A good seal means the cup is working, but sometimes that same suction makes it a little harder to remove the first few times. Don’t pull the stem directly: first pinch the base to break the vacuum, then remove it gently. We explain it in full detail, including tricks to avoid stains, in how to remove the menstrual cup with no stains and no tugging. And if you ever feel you can’t reach it or that it has “gone up”, there’s no need to panic: we have a calm guide on what to do if your menstrual cup feels stuck.

Why nobody explains this clearly the first time

Here’s a curious fact: most instructions that come with menstrual cups stop at “fold it and insert it”, without explaining what you should feel afterwards. No wonder it raises questions. People who switch to the cup and learn to recognize these signs often wonder why nobody explained it to them in this much detail before — probably because the disposables industry has no interest in you understanding a product that, bought once for €15-20, lasts you years with no monthly repurchase.

With practice, checking that it’s properly placed stops being a conscious process: within two or three cycles you’ll know just by getting up from your chair. If you also have general questions about the product, this is a good moment to go over the most common myths about the menstrual cup or our menstrual cup FAQ.

Basic care so it keeps sealing well cycle after cycle

A poorly cleaned cup can lose effectiveness over time: dried residue in the small air holes (if your model has them) or on the rim can interfere with the seal. Wash it with water and a specific mild soap between uses within the same cycle, and boil or sterilize it between cycles. You’ll find the whole process, step by step, in how to sterilize a menstrual cup.

For daily hygiene while you’re using it, avoid vaginal douches and perfumed soaps: they can upset your pH and lead to discomfort. MedlinePlus information on feminine intimate hygiene recommends lukewarm water and, at most, a mild soap for the area.

Does anything change if you exercise, sleep or swim with the cup?

No, and this often surprises beginners. Once the menstrual cup is properly placed and the seal has formed, movement doesn’t shift it: you can run, do yoga, swim or sleep in any position without affecting the suction. In fact, a pelvic floor that tightens during exercise usually helps keep it in place, not the other way round. What does change with activity is how often you empty it if your flow is heavy that day, but not the way it should sit.

Another common question is whether the feeling changes over the cycle. It’s normal: in the first days, with more flow, you’ll notice sooner that it needs emptying, but you still shouldn’t feel the cup while it’s in. If at some point in your cycle it feels different — lower, higher, less comfortable — it’s usually down to natural changes in pelvic floor tone or in the position of your cervix over the month, not to you having “forgotten” how to insert it.

Summary: your quick checklist before leaving the house

• Do you feel it when you walk? You shouldn’t.
• Does the stem barely show? A slight touch is normal; pain isn’t.
• Do you feel the vacuum when you pinch the base? That suction is proof of the seal.
• Does it rotate effortlessly? That confirms it’s fully open.
• No stains in the first few hours? That’s the final confirmation.

If you tick these five boxes, your menstrual cup is exactly where it should be. And if one of them ever fails, you know which article to come back to.