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Know Your Flow: How Heavy is Too Heavy?



5 min read

Thinx - Periodical - Know Your Flow- How Heavy is Too Heavy?

by Toni Brannagan | 02/24/2021

Let’s be real, you’ve probably looked down during a particularly crampy day 2 or 3 of your period week and thought, dang. How am I not dead?

Periods vary from cycle to cycle, and certain months will be lighter or heavier, but that doesn’t mean that you’re not gonna give an *extra* heavy flow a second thought. Sure, periods and heavy bleeding are natural and all that, but it can really look like a whole lot of blood down there! 

To avoid any future frantic calls to your gynecologist at 10 p.m. because you were worrying about blood loss and if your vagina was broken all day, but tried to ignore it, and you definitely should have called earlier when it was still office hours — this is still a universal experience, right?? — here are some things to keep in mind:

what is "normal" anyway?

First of all, if you’ve noticed that your period is irregular, good on you! That means you know what your normal menstrual cycle is, and that’s the only normal that really matters. 

Chances are, you’re not sitting around comparing the aftermath of vaginal bleeding with your friends, but if you were, it wouldn’t really help you learn anything about your body. *Every body* is different, including our periods.

What’s really important is knowing when your body is trying to get you to pay attention — an irregular period with a heavy menstrual flow can definitely be a warning sign.

is it possible to bleed too much?

If we wanna get science-y about it, the typical amount of menstrual blood you’ll lose over an entire period (an average of 4-6 days) is less than 80 mL. That translates to about 16 teaspoons, in case you’re like me and mL means literally nothing to you. 

You probably think that you’re bleeding a whole lot more, but that’s because menstrual flow *isn’t* just period blood; it’s also composed of tissue, mucus, and other fun stuff that goes along with your uterus shedding its lining.

You should start paying attention when your flow when it goes past the 80 mL point. This point is considered heavy menstrual bleeding, which can be a medical condition or a sign of hormonal imbalance. Since you probably don’t have a graduated cylinder between your legs all period long, the National Health Service suggests to take note of a heavy period if you have to change your period products every hour or two, or if you’re passing large clots.

The clinical name for regularly heavy periods is menorrhagia, which is commonly caused by high estrogen and low progesterone.

symptoms of menorrhagia include:

  1. Bleeding for longer than one week

  2. Having to get up at night to change your pad or tampon

  3. Having to change your sanitary products every hour or so during the day

  4. Passing blood clots for more than one day

  5. Experiencing symptoms of anemia (tiredness, shortness of breath, fatigue)

  6. Having trouble sticking to a regular schedule because of your flow

other causes of heavy periods

A consistently heavy flow, especially if your period changed over time, can be a symptom that something else is amiss, including the following:

  1. Side effects of certain medications (especially ones that interfere with blood clotting)

  2. Fibroids (growths on the uterus)

  3. Polyps (growths on the uterine lining)

  4. New birth control: While your body gets used to a new hormonal contraceptive such as a birth control pill, your period may be irregular. The copper IUD can also cause periods to be heavier.

  5. PCOS (polycystic ovary syndrome)

Causes can also include more serious issues like complications with pregnancy and, more rarely, cancer.

okay, so should I call my gyno?

If you notice an unusually heavy menstrual flow once or twice, keep an eye on it, and also consider whether you’ve recently gone through any large life changes, lost or gained a significant amount of weight, or started/stopped any medications. 

There are a number of factors that can throw off your menstrual cycle (sometimes, it seems like even a light breeze will do the trick), but knowing what’s potentially messing with your flow will help give you peace of mind, and will make it easier to update your doctor — whether that’s during your next annual, or if you schedule a check-in.

No matter what, if you’re in any amount of pain, you should give your gynecologist a call. A heavy period and painful period cramps are often an indicator of something that’s going untreated, like a few of the things we listed above, and your gyno will be able to help you figure out how to manage it best. 

Do you ever feel like your period is *too* heavy, or stop and ask yourself, "why is my period flow so heavy?" How have you handled irregular flows in the past? Share with us in the comments.

Toni Brannagan is a writer and was the former Copy and Content Manager at Thinx.

At Thinx, we strive to provide our readers with the most up-to-date, objective, and research-based information. Our content is crafted by experienced contributors who ground their work in research and data. Articles contain trusted third-party sources that are either directly linked within the text or listed at the bottom to lead readers to the original source.

by Toni Brannagan

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