- Menstrual discs may be the best option for people with heavy menstrual bleeding, new research shows.
- A new study compared the absorbency or fillable capacity of 21 different menstrual products on the market right now.
- Heavy bleeding is quite common among people who menstruate, but it could be indicative of an underlying condition and should be evaluated by a medical professional.
For people with heavy periods, menstrual discs might be the best choice in more ways than one, researchers say.
For a new study, published last week in the journal BMJ Sexual & Reproductive Health, scientists tested the absorbency or fillable capacity of different menstrual products on the market right now, using blood instead of water or saline.
Menstrual discs were the clear winners, holding the most blood at 61 milliliters. Meanwhile, absorbent period pants held the least amount of blood at just 2 milliliters, on average. Tampons, pads, and menstrual cups all held about the same amount, ranging from 20–50 milliliters.
Though knowing the capacity for certain period products is useful purchasing information, it may also better help doctors quantify menstrual blood loss to see which patients might benefit from additional evaluation or monitoring, according to experts.
Here's what to know about the new research, and how the new information can impact a person's reproductive health.
What Is a Menstrual Disc?
Menstrual discs are period products that fit inside your vaginal canal, just beneath your cervix, according to Christine Greves, MD, a board-certified ob-gyn at the Winnie Palmer Hospital for Women and Babies. The discs have a firm, round rim with a more flexible center that collects period blood. They’re reusable and typically made from medical-grade silicone.
Heavy Menstrual Bleeding Is Common, but Sometimes Difficult to Diagnose
Among people who menstruate, heavy bleeding is quite common. About one-third of menstruating people seek treatment for heavy flows—but extremely heavy periods aren't considered normal and could be a sign of an underlying condition like fibroids and bleeding disorders.
Currently, heavy menstrual bleeding can only really be diagnosed through more traditional period products, like tampons and pads. According to the American College of Obstetricians and Gynecologists, the following are signs of heavy menstrual bleeding:
- Bleeding that lasts more than seven days
- Bleeding that soaks through one or more tampons or pads every hour for several hours in a row
- Having to wear more than one pad at a time to soak up menstrual blood
- Getting up at night to change pads or tampons
- Period blood that contains blood clots that are the size of a quarter or larger.
These criteria are based on what's known as the Pictorial Blood Loss Assessment Chart (PBAC), which only includes information on the absorbency capacity of pads and tampons. But what the chart doesn't take into consideration is newer period products like menstrual cups, pads, and absorbent period pants. That's where the new research comes into play.
According to study co-author Bethany Samuelson Bannow, MD, she and her colleagues decided to test the capacity of additional period products when they realized they didn’t have a good metric to diagnose heavy bleeding in menstrual cups and discs, similar to what’s known about pads and tampons. That turned out to be a problem, especially as more women are opting for alternative products.
"I practice in Oregon and take menstrual histories on virtually every patient I see,” said Bannow, who works as a hematologist who specializing in caring for women with bleeding and clotting disorders at Oregon Health & Science University. “We have noticed that a lot of folks—particularly those with heavy periods—are moving toward cups and/or discs."
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Menstrual Discs As the Clear Winners for Period Blood Capacity
For the new study, Bannow and her colleagues tested a variety of commercially-available menstrual products—21, to be exact—in laboratory to determine how much blood they could hold. The products included pads, tampons, menstrual cups, menstrual discs, and super-absorbent period pants. The blood used was expired human packed red blood cells.
Menstrual discs had the greatest capacity for blood, being able to hold 61 milliliters, on average (one brand of menstrual disc, Ziggy, held the most blood at 80 milliliters). Tampons, pads, and menstrual cups all held similar amounts, ranging from 20–50 milliliters each. Absorbent period pants came in last, holding just 2 milliliters of blood.
The study authors also noted that there were inaccuracies between what period products claimed to hold versus their actual capacity.
"The majority of products reported that they had greater capacity than our testing found," the authors wrote. "We suspect this is due to product testing with non-blood liquids, such as water or saline."
Authors of the study also acknowledged that it had a few limitations, including how tests results from a lab aren't the same as obtained on real people.
The blood used was also a limiting factor. The human packed red blood cells are just red blood cells separated from whole blood, but it's different than menstrual blood, which also contains endometrial cells and vaginal secretions. It's still better than using water or saline to test period product capacity, which is what's been used in the past, said the authors.
Still, the authors said that the new findings and future information like it "can help clinicians better quantify menstrual blood loss, offer diagnostic testing, and accurately treat [heavy menstrual bleeding."
More Research on Menstruation Is Needed
Menstruation has historically been somewhat of a taboo subject, argue doctors in the department of obstetrics and gynecology at Stanford University in a linked editorial to the new study. In some countries, women are even excluded from daily activities or discriminated against in other ways. This has hindered research on the subject, despite the fact that 800 million people around the world are on their periods every single day.
"Consistent with women's health research in general, menstruation-focused research has been, and continues to be, underrepresented in the medical literature," authors of the editorial wrote.
The doctors pointed out the discrepancy between women's sexual and reproductive health research and men's sexual and reproductive health research. Since 1941, only 400 studies have been published relating to menstrual blood. Meanwhile, 10,000 studies have been published related to erectile dysfunction.
Not only is more data needed to potentially aid in improving the lives of people who menstruate, but also to understand how menstrual blood may be an important diagnostic tool for endometriosis, diabetes, and human papillomavirus (HPV).
"With so many future possibilities for deriving clinical value from menstrual blood, one can almost imagine a future in which menstrual stigma is replaced by clinical opportunity," the authors wrote.
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Seeking Medical Advice for Heavy Bleeding
Despite how common heavy bleeding is among people who menstruate, it should be evaluated by a healthcare provider.
“Anyone with heavy periods interfering with their quality of life should be evaluated by a physician, rather than just trying to find a higher capacity product,” Bannow said.
Heavy menstrual bleeding can be a sign of an underlying health issue, including fibroids, bleeding disorders, or endometriosis; but the heavy bleeding itself can also lead to iron-deficiency anemia.
When evaluating heavy menstrual bleeding in patients, ob-gyns may conduct a physical exam, along with lab tests and imaging tests like an ultrasound exam or magnetic resonance imaging (MRI).
First-line therapies for heavy menstrual bleeding include hormonal birth control and pain relievers like nonsteroidal anti-inflammatory drugs (NSAIDs). In more severe cases, other medications, like hormone therapy, may be tried; surgery may also be an option for some patients.