Inserting Your Menstrual Cup Wrong Can Be Dangerous—Here’s How to Use One Correctly

Menstrual cups are a popular and more sustainable way to manage your period. But a new case study has experts reminding people about the importance of using them properly.

A BMJ report published this month outlined the case of a Danish woman in her 30s who was treated for pain in her right side and lower abdomen, as well as blood in her urine. She’d been experiencing these symptoms a few times each week—each episode lasting about an hour—for six months.

After running tests, scans, and interviews with the patient, doctors theorized that the woman’s pain and bleeding were caused by her menstrual cup. They asked her to stop using it, and after a month, her symptoms had cleared up.

“The CT scan [showed] that the cup was positioned in the right side of the vagina, thereby compressing the opening from the ureter to the bladder. The ureter is the tube that drains urine from the kidney to the bladder,” study author Clara Maarup Prip, a urologist at Aarhus University Hospital, told Health.

Essentially, the menstrual cup was obstructing the flow of urine from the woman’s right kidney to her bladder, causing inflammation and other symptoms, Prip explained.

Blood in urine due to an improperly placed menstrual cup is extremely rare, said Jillian LoPiano, MD, MPH, OB/GYN and chief health officer at Wisp, a reproductive healthcare telehealth company. There have only been a few other reported cases of this happening, she explained.

In fact, a number of factors have to align for this complication to happen, added Michael Baldonieri, MD, OB/GYN generalist at University Hospital Cleveland. Those include the “size of the cup, positioning within the vagina, length of usage, and the patient’s specific anatomy, which make this very unlikely to occur with regular cup usage,” he told Health.

However, the case report is a good reminder of the importance of proper menstrual cup placement and use, experts agreed.

“[We need] more awareness about possible complications and the presenting symptoms of these complications, both among menstrual cup users and clinicians, [as well as] more awareness of the importance of choosing the correct shape, size, and insertion method,” said Prip.

Typically made of medical-grade silicone or thermoplastic elastomers (TPE), menstrual cups are small and flexible so they can be inserted into the vaginal canal, similarly to a tampon. The cup catches menstrual blood as it flows.

“The small, bell-shaped, reusable device is designed to create a small amount of suction to prevent leaks while collecting menstrual blood,” said Lopiano.

People can use these cups for up to 12 hours before they have to be emptied, cleaned, and reinserted. Many are intended for long-term reuse—some may last up to a decade. However, there are disposable ones on the market, too.

Because of this, menstrual cups are becoming increasingly popular.

“Recent studies show menstrual cups are used by 19% of those who menstruate, and mostly by those in their 20s and 30s,” LoPiano explained.

However, it depends on the population, Baldonieri added. “In the United States, roughly 10% of menstruating people use menstrual cups. Rates of usage can range from 7% of menstruating Turkish people, to about 23% of Brazilian undergraduate students,” he said. “[There] is significant geographic variability.”

The fact that menstrual cups aren’t as widespread as pads or tampons is due to a number of factors, but there are some drawbacks to using the product.

For one, menstrual cups may be difficult or uncomfortable to change in public restrooms since users need to rinse them out and ensure they’re cleaned properly before reinserting them.

“Menstrual cups need to be cleaned thoroughly between uses to prevent the buildup of bacteria,” the Alliance for Period Supplies, a national organization focused on providing greater access to period products, said on their website. “This can be time-consuming and requires access to clean water and a cleaning solution, such as mild soap or a specialized cup cleaner.”

Women who use intrauterine devices (IUDs) should also talk to their doctor before using menstrual cups—in rare cases, they can dislodge IUDs.

In general, there haven’t been many complications from menstrual cup usage. However, it’s possible that people could experience infections, pain, vaginal wounds, allergic reactions, period blood leakage, urinary incontinence, or toxic shock syndrome.

Despite menstrual cups’ growing popularity, research has shown that it’s difficult for women to make an informed choice about which menstrual cup product they should use or how to use it properly.

In 2021, U.K. researchers concluded: “With no correlation between menstrual cup size, shape, and its volume, or material, shape, and its firmness, consumers cannot estimate which menstrual cup might be most suitable, and incorrect choice could cause injury.”

If you have questions about whether you should use a menstrual cup or which one to try, your gynecologist should be able to give you some guidance.

Once you do start using a menstrual cup, it’s important to insert it properly. Just know it may take some getting used to—a 2019 study found about one in four women had issues using a menstrual cup for the first time, though most felt comfortable with the product by their third cycle of use.

Before you insert a menstrual cup, first wash your hands with soap and water. Then, fold the product—most use a C-fold, in which you fold the cup in half to form a “C” shape. But there are other insertion strategies too, including a 7-shape fold, a half-diamond fold, and more.

“The menstrual cup should sit just below your cervix—should sit lower than a tampon—but not be noticeable outside the body or feel uncomfortable,” said LoPiano.

Once properly placed, the cup will open up and fit well against the walls of the vagina with a slight suction.

“Most cups have a stem at the base to aid in removal, and this should sit just inside the vaginal opening, so it is not visible once placed,” said Baldonieri.

In general, you shouldn’t be able to feel a menstrual cup while you’re using it, LoPiano said. However, when first starting to use the product, you might have slight awareness or discomfort as your body adjusts.

“Most people have no pain once they learn how to use it,” she said. “If you are feeling any pain or significant discomfort, it is most likely being placed wrong or is too large or small.”

When it’s time to remove the menstrual cup, press the sides of the cup to help ease the suction, then slowly pull it out to avoid spilling blood. Then empty the blood into the garbage, toilet, or sink before rinsing the cup thoroughly with warm water and soap. Then you’re ready to reinsert it.

Of course, menstrual cups are just one of many ways to manage your period. And because every person has slightly different anatomy, there is no one-size-fits-all solution to menstrual cups or period products in general, Baldonieri said.

“Periods are as unique as the person experiencing them. The best option for period management is the option that is most comfortable for you,” he said. “If any of your menstrual products cause pain, I recommend a consultation with your OB/GYN.”