Which menstrual cup firmness is right for you? Well, for starters you might not even know that period cups have firmness. The resistance a cup has while squeezed is its firmness. The durometer (a scientific score for the hardness/softness of materials like silicone also called a shore score) plays a large role in a cup’s firmness. Other factors include the shape of the cup and the thickness of the rim. For the purposes of menstrual cup and menstrual disc firmness, we are primarily referring to the rim and the non-scientific firmness score over durometer.
Categories of Firmness
- Softest – This cup is flimsy and can easily be folded multiple times over.
- Soft – This cup can be folded easily but is not “flimsy”
- Average – Not too soft, not too firm. Opens with some force but is also easy to fold.
- Firm – This cup opens with some force and is less easy to keep folded.
- Firmest – This cup is difficult to fold and keep folded. It opens with lots of force.
Why Menstrual Cup Firmness Matters
- Ease of opening
- Wear and staying in place
Firmness and Cup Opening
When you insert a menstrual cup the ideal scenario is that the folded cup will open fully inside the vaginal canal without additional manipulations. A cup is only effective when it’s open and sealed. The firmer the cup the easier it is for that cup to open in the body. Remember – your vaginal canal gives way to the cup’s size. Your body stretches slightly to accommodate a cup. A firmer cup applying “outward force” when it opens in the body is more likely to seal.
Cups that are 1. Softest or 2. Soft will have more trouble opening in the body without manual assistance.
Cups that are 3. Average, 4. Firm, or 5. Firmest will open easier inside the body, especially cups in the Firm or Firmest category. This is because the cups have more outward force when unfolding as they want to go back to their natural molded shape.
Comfort and Firmness
Most users will find cups from the 1. Softest up through the Average categories the most comfortable. Firm or Firmest cups apply an outward pressure that can affect comfort. This presents in a few ways.
- Bladder Pressure – user feels the urge to urinate
- General Pressure – user feels the cup inside their body
- Slow Urination – user finds that urinating is slower
- Rectal Pressure – user finds it hard to have a bowel movement
The right menstrual cup for you should be completely undetectable in your body. If your menstrual cup is too firm and applies a detectable pressure in your body that causes discomfort you will want to find a softer cup or a reusable menstrual disc. Menstrual cups apply pressure to your bladder/urethra due to where they’re worn in your body. If you don’t want a softer cup then a menstrual disc of any firmness is likely not to cause pressure. It sits in a different part of your anatomy.
Do be cautioned that there is an anecdotal (very rare) correlation between cups that are too firm restricting urine flow and an increase in UTIs.
The trade-off of using a softer cup is that it might be harder to get open and sealed, but the comfort is usually worthwhile, especially for experienced cup users. It’s very common to begin with an Average or Firm cup and switch to a Soft cup.
Longtime Wear and Slippage in the Body
Menstrual cups are held in place by a combination of your pelvic floor muscles and the “suction” created by the vacuum of the cup’s seal in your vaginal canal. Firmness is an additional component that makes this equation work. For a cup to stay in the body without slipping there is a 3 legged table of “musts” that have to occur. If even one of the legs is broken the cup is more likely to slip down during wear.
If your pelvic floor is very toned your everyday movements during walking or running can be strong enough to push against the cup. Certain cups are more affected than others but many users notice that softer cups can be pushed down easier than firmer cups. That said, the opposite can also be true and the softer cup absorbs the pressure of the muscles and stays put.
As a general observation, it’s more likely that a firmer cup in the Firm or Firmest category is going to stay in place when your pelvic floor is very tone.
If you’re less active or not at all active a cup in the Average or Soft category will usually be a better option and stay in place during your normal activity.
Unless you have experience using other menstrual cups I wouldn’t try a 1. Softest cup as a first-time user. These can be frustrating to use and are more prone to slipping during wear. Many extremely “cheap” cups are Softest in firmness and new users don’t succeed because of the way this firmness works in the body and struggles to open.
For those who do high impact exercises, you may want to look into menstrual discs, which stay tucked behind the pubic bone and are less likely to be pushed downward during certain physical movements. As always, wear backup such as trim period underwear with a new menstrual product during your workout routine until you’re sure it stays leak-free!
Need more guidance on how to pick the best menstrual cup for you? Try the expertly designed Period Nirvana Cup + Disc Quiz. Size, shape, firmness, capacity, and length are all taken into consideration in your results. You can also visit our sortable menstrual cup chart and explore firmness scores alongside other product attributes.