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Period Products Are Not Tested Using Real Blood. (Yes. You Read That Right.)

One groundbreaking study finds absorbency levels may be misleading. Here’s what you need to know.

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In 2020, a period product company used red liquid to show how absorbent their sanitary pads are in a TV commercial. It was the first time a mainstream company in the U.S. swapped the typical blue liquid for red to represent period blood.

After the advertisement aired, some people took to social media to applaud the realistic representation.

But that’s all it was. A representation.

In reality, manufacturers test the absorbency of period products using saline — a mix of water and salt — and not actual blood.

This fact was recently noted in a 2023 study where four female researchers at Oregon Health and Science University (OHSU) used human blood to test the accuracy of absorption in period products — for the first time ever.

Read: What’s Normal When It Comes to Menstrual Bleeding? >>

As you might imagine, the study received a lot of attention. If you didn’t know this mind- boggling nugget about period products before now, it can be a lot to process. Although the lack of industry testing with actual blood may be shocking to some people, Bethany Samuelson Bannow, M.D., co-author of the study and an associate professor of medicine at OHSU, wasn’t fazed. “I'm never super surprised when things haven't been done in women’s health,” she said.

Heavy menstrual bleeding and health concerns

The study also raised eyebrows regarding the results. Researchers found that a majority of the existing absorbency labels on period products that had been tested with saline indicated that they could hold more compared to what researchers found during testing. This mismatch is because blood and saline have different physical properties and are absorbed at different rates. What that means is that using the estimates on the label for most period products will result in an underestimate of the blood loss the menstruator is experiencing.

These findings are especially concerning considering that heavy menstrual bleeding is typically diagnosed based on a person’s experience with their period products. “The important thing to note is the distinction between medically diagnostic tools and products used for other purposes. So if I’m going to check someone for thyroid disease, I’m going to send them to a lab and do a test that was specifically created for that purpose. But when we are diagnosing heavy periods, we are really dependent on reports of what patients are using,” Samuelson Bannow said.

Read: I Thought My Heavy Bleeding Was Normal — Until It Almost Killed Me >>

And if people think their products hold less blood than they actually do, that could mean people with heavy menstrual bleeding are going undiagnosed. This is a serious problem because heavy bleeding can lead to anemia, or a lack of iron, which can cause fatigue, headaches and weakness among other issues. Heavy bleeding can also be a symptom of other serious health concerns such as endometriosis, fibroids and some gynecologic cancers.

Read: Comic: Annie Has Anemia >>

To diagnose heavy menstrual bleeding, healthcare providers (HCPs) also use the pictorial blood loss assessment chart (PBAC) so people can tell their HCPs how saturated their pads or tampons are. But, once again, this is flawed if providers are assuming that a “full” pad or tampon holds more than it does. (The PBAC doesn’t include newer period products like menstrual cups. And menstrual cups are commonly used among people who have heavy periods, Samuelson Bannow said.)

“I hope [the research] helps make people aware of the varied ability of these products and I hope that changes how [healthcare providers] look at history taking,” Samuelson Bannow said.

Heavy menstrual bleeding and mental health

Heavy periods can bleed into all aspects of life and have a negative affect on mental health too. “Bleeding heavily can cause women stress — worrying about bleeding through products and onto clothes, the cost of buying products [and] just the weariness that heavy bleeding can cause,” said Heather Bartos, M.D., an OB-GYN and member of HealthyWomen’s Women’s Health Advisory Council. “Heavy bleeding can also affect a woman’s sex life.”

If you think you may have heavy menstrual bleeding, it’s important to talk to your HCP about your symptoms. “A simple ultrasound and labs can usually diagnose the issue, and there are many options to control the bleeding — not just contraceptives — but also newer treatments,” Bartos said.

It’s still tough to think that an essential product that all menstruators will use at some point in their life has been developed without using the very thing it was made for. Periods are natural. And people who menstruate deserve products and healthcare options that reflect this normal — however complicated — part of life.

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