I’ve heard from so many people how they tried their first menstrual cup, and sadly, it didn’t work for them. Maybe this is you, or perhaps you’re afraid to buy a cup because there are so many choices available on the market, and it’s hard to know which one to pick.
Not all bodies are the same, so not all menstrual cups work for everyone. Maybe the problem isn’t that the cup doesn’t work for you but that you simply haven’t found the right fit.
Finding the best menstrual cup is a bit of a trial and error process, but let’s face it, a cup is a significant investment, and trying out several until you find THE ONE isn’t fun.
To help you narrow down your choices, I’ve put together a guide with 3 things to consider when choosing the best menstrual cup.
Here’s what you’ll find in this article:
Here’s what you’ll find in this article:
1) The length of the cup

The length of your cup is directly related to the height of your cervix, and it’s the most important aspect of picking a cup.
Your cervix is a narrow neck-like passage that leads to your reproductive system, allowing sperm to enter your uterus or menstrual blood to leave. It’s positioned at the end of your vaginal canal and looks like a little pink doughnut.
Why is it important to measure the cervix?
Your menstrual cup will sit in your vaginal canal, below your cervix. Knowing the height of your cervix is essential to find a cup with the right length and make sure that a) you’ll be able to reach it or b) it won’t peep out.

How to measure your cervix?
The first thing you need to know is that the position of your cervix changes depending on the phase of the cycle you’re in. So, measure it when you’re close to or on your period, as it’s more likely to be lower and more reachable.
1) Wash your hands very well, and avoid applying moisturizers before feeling your cervix.
2) Find a comfortable position, maybe squatting, sitting on the toilet, or putting one leg on the toilet seat or chair. When you’re ready, gently insert your index finger into your vagina, as far as it will go.
3) What you’re looking for is the firm doughnut shape of your cervix which usually feels like the tip of your nose. While the vagina walls feel soft (like the inside of your cheeks with possibly some ridges), the beginning of the cervix feels firm (like the tip of your nose).
- If you touch your cervix by your first knuckle, consider you have a low cervix.
- If you touch your cervix by the second knuckle, consider it an average height.
- And if you touch your cervix up to or beyond your third knuckle, or if you can’t reach it, consider it a high cervix.

Alternatively, you can measure the height in millimeters, giving you a more accurate idea. Once you reach your cervix, mark it with your thumb (place your thumb right inside your inner lips), take out your finger and measure the distance from your thumb to the tip of your index finger with a ruler or a measuring tape.
- 44 mm or lower: low cervix.
- Between 44-55 mm: average height.
- 55mm or higher: high cervix.


4) With your measurements in hand, finding the best menstrual cup will be easier. Most brands indicate the length in mm and specify if they’re designed for low, average, or high cervix.
Ideally, you want to find a cup that sits lower than your cervix (without being too short that you can’t reach it), or if you have a low cervix, a cup that sits around it.
By the way, did you know that it’s perfectly fine to trim the stem?
If you find it annoying and can remove your cup without it, feel free to get rid of it!
2) The diameter of the cup

Now that you know the height of your cervix, it’s time to check the cup’s size.
Brands usually offer different sizes; some call them “small, medium & large”, or “1 & 2”, or “a & b”, etc. – I know, it’s confusing! When they refer to size, they talk about the diameter, not the length.
The typical guideline suggests that if you’re under 30 years old and haven’t had a full-term pregnancy, you should pick a smaller size, but if you’re over 30 and/or have had a full-term pregnancy, you should choose a larger one.
While this is helpful, it may not be entirely accurate for you. A small size can be just fine if you know you have a strong pelvic floor despite your age or birth history. And if you’re not sure, go for a larger size! Your vagina has an amazing capacity to stretch – it can easily accommodate a larger cup but can’t shrink to hold a smaller one.
3) The capacity of the cup

Finally, you need to know how much you bleed every cycle to choose a cup with a suitable capacity.
The average menstrual blood released in a cycle is 30-60 ml (about 2-4 tablespoons). Menstrual cups have an average capacity of 25-30 ml (it actually holds more than a super tampon!), which should be enough for most people. Having said this, you could have a heavy period and need a larger model cup.
It’s essential to measure how much you bleed each cycle objectively. Check my article Your menstrual blood says a lot about your health for a guide on measuring your flow.
Most brands indicate how much flow they hold. Usually, the cup can be emptied every 12 hours. Still, if your periods are more on the heavy side, you might need to do it more frequently, especially during the first two days of your bleeding. Using it together with a good pair of period panties can be a good idea too!
Putting everything together
The three things you need to consider to find the best menstrual cup are (in order of importance):
Aspect | What to choose | Before buying your cup |
---|---|---|
The length | Find a cup that fits within your vaginal canal comfortably. | Measure your cervix. |
The diameter | Pick the one that fits diameter-wise. When in doubt, go for a larger size. | Consider your age, if you’ve had a full-term pregnancy, and most importantly, how strong your pelvic floor is. |
The capacity | Pick the one that holds enough blood depending on how much you bleed. | Measure objectively how much flow you release in one cycle. |
Putting everything together
The three things you need to consider to find the best menstrual cup are (in order of importance):
1) The length:
Find a cup that fits within your vaginal canal comfortably.
Before buying your cup: Measure your cervix.
2) The diameter:
Pick the one that fits diameter-wise. When in doubt, go for a larger size.
Before buying your cup: consider your age, if you’ve had a full-term pregnancy, and most importantly, how strong you feel your pelvic floor is.
3) The capacity:
Pick the one that holds enough blood depending on how much you bleed.
Before buying your cup: Measure objectively how much flow you release in one cycle.
An amazing resource to make the process even easier
Still too overwhelming? I got you!
I hope after reading this, you have a better idea of how to find the best menstrual cup for you. But I know all this information can feel like too much, so I want to share an incredible resource with you:
Put a Cup in it has created a free quiz to help you find the best menstrual cup, depending on your needs. All you need to do is answer a few questions, and at the end, it will suggest 3 or 4 alternatives — you might even get a discount code to buy your cup! You can check it out here.
(This content is not sponsored; I just find it super helpful!)
And if you have any questions, you can always comment below or contact me on Instagram at @carlorenzana.

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