Menstrual cups can be worn safely for up to 12 hours at a time, but your cup may fill up well before that. And people with heavy periods may need to empty their menstrual cups sooner than others.
So, how do you know how often to empty a menstrual cup? How do you know if your cup is full?
You’ll have to make educated guesses and learn to recognize your period patterns. The first step is figuring out how much blood you lose over a few hours versus how much the cup holds. If you follow these tips, you’ll soon have a good routine for emptying your menstrual cup.
How Heavy Is a Normal Period?
The average volume of menstrual fluid shed each cycle ranges from 30 to 80 milliliters (up to 6 tablespoons.) If you just gasped in disbelief because this feels too low, then you are certainly someone with a heavy period. A 2001 study quantified losing over 100 milliliters of blood as “excessive” and 60 to 100 milliliters as “moderate.”
A recent viral Twitter thread started by @SlimGirlSupreme explored this topic with the question, “are you guys sure when we menstruate we are only losing 2-3 tablespoons of blood because that sounds very FAKE to me.”
The replies definitely agreed that the “average” amount of lost period blood feels awfully low compared to lived experiences.
Menstrual cup users have a unique insight into their own periods and can often tell you exactly how much volume they lose. It’s not unheard of for someone to lose more than 100 milliliters in a single day. The average menstrual cup holds about 30 milliliters, so this would mean the cup needs to be emptied four times in a single day, at minimum.
How Often Do I Need to Empty My Menstrual Cup?
You can usually feel when you need to switch a pad or tampon. Switching to a cup means learning when and how often to empty your menstrual cup.
Many years ago, a company called LoonCup invented a smart bluetooth menstrual cup that alerted your phone when it needed to be emptied. It had a successful Kickstarter but was never manufactured or sold.
But honestly, you don’t need a notification. You just need to get to know your period.
Related Resource: Menstrual Cup Cleaning Guide
Check for Signs That Your Menstrual Cup Is Full
In most cases, you can’t tell how full your menstrual cup is. However, there are some users who report tell-tale signs that they need to empty their cup. It’s more common to be blindsided by a full cup than feel any detectable warning signs. Some of these signs can also be related to a cup that doesn’t fit well, so take this list with a grain of salt:
- A “heavy” feeling. Your pelvic muscles feel tired after holding a cup that is full.
- A bubbling sensation. Cups that are about to overflow can create a feeling of bubbles.
- Light warning leaks. If the cup is at capacity, you may see signs at your next toilet visit.
- A slipping cup. If the cup fit fine earlier and is now slipping, it might be a sign it’s full.
Experiment During Your First Period With a Menstrual Cup
On Day 1 of your first period using a menstrual cup, remove it after 2-4 hours. If you know you have a heavy period, check it after 2 hours. If your period isn’t heavy, you can wait until the 4-hour mark. As a new user, it’s better to be safe and check early than wait the full 12 hours and be greeted by bloody undies instead.
After removing your cup, give it a thorough look. This may even be your first time seeing your menstrual blood without it being soaked up by cotton. Some people find this fascinating, and others are not fans of seeing blood.
Notice how empty or full your cup is, and note how long it took to get to this level.
If your cup is half full or less, there is a good chance you can go 8-12 hours before needing to empty your cup.
If the cup is nearly full, continue removing it every 2-4 hours on heavy days to avoid overflowing.
Benefits of Using Menstrual Cups for Heavy Periods
Even if your period is extremely heavy, you can use a menstrual cup.
For one thing, menstrual cups hold more blood than tampons. Someone with an extremely heavy period who is used to changing a super tampon every 30 minutes to an hour will find more freedom with a cup that only needs emptying every 2-3 hours.
You can also explore menstrual cups for heavy periods that hold more than average cups. A higher-capacity option or menstrual discs that allow for “self-emptying” can extend your wear time to make periods more manageable when they’re extremely heavy.
Another benefit to using a cup for heavy periods is your newfound set of quantifiable data. In many cases, health professionals can be dismissive of period problems. As a cup user, you can provide exact measurements of how much menstrual fluid you’re losing per cycle. If you find yourself filling a menstrual cup hourly, this is proof of an extremely heavy period.
Changing a tampon every 2 hours is already considered “extremely heavy,” so changing a cup every 1-3 hours is something to discuss with your doctor. There may be an underlying medical reason behind your heavy periods.
The Learning Curve
After several cycles, typically two to three, you will fully understand your period and how often to empty your menstrual cup each day. You may find that on the 1st and 2nd day, you need to remove the cup every 4 hours, but on days 3, 4, and 5, you can keep it in the full 8-12 hours.
While you’re learning how often to empty your menstrual cup, it’s a good idea to wear back up liners or period underwear. If you overflow the cup or experience a leak for any reason, you will be protected.
I have a very heavy period. I can fill a hello disc 3 times in 24 hours for the first 2 days. It declines after that but if you add that up it’s roughly 400 ml in the first two days. Eek. That doesn’t seem right! I think I’m going to keep track of it this period so I can give that info next time I go to the obgyn because they never seem to believe how heavy my period is. On a side note, one problem is that during the first two days of my period, my cervix is super low! Like 40 ml. So sometimes it’s a fight to get my hello disc in. I’ve added the Merula OS to have on hand on days when my cervix isn’t feeling like using a disc.
‘Measuring’ your flow is one side benefit of re-usable products. Pads and Tampons can hide how much your flow you actually produce. I would certainly have the conversation, and I’m glad that you found a few re-usable products that work for you. Switching products for different parts of your period is totally OK; you could even throw in re-usable underwear into your rotation. Best of luck.
Sometimes I get the bubbling feeling or light warning leaks when I go the the bathroom, but my cup is never more than half full, even when I get these signs. Could I need a different type of cup? I use both the Saalt regular and soft.
If the cup is performing well for you otherwise, I wouldn’t worry about replacing it because you’re getting the bubbling feeling too early. If you feel like the warning leaks are a fit issue, I would recommend quizzing our Period Nirvana Facebook community to suss out a potential solution.
I have been using a menstrual cup for over 10 years.
This week I decided to try pads to let it “breathe” and flow out naturally. I’m home all week so might as try it now.
But what I am noticing is that the blood seems to come out ONLY when I go to the bathroom – it’s as if it thinks there’s a cup inside. It is quite odd. I don’t know how I feel about it. I don’t know if anyone else has experienced this. Maybe in time my body will “reset” down there. Who knooooows.
The only theory I have is that it was held in by your labia, and squatting/using the restroom might provide room for things to vacate. Some folks may envy your situation, I wouldn’t worry about it so long as you’re prepared.