Doctors warn against ill-fitting menstrual cups

A new case study details a rare but serious consequence of using a menstrual cup that is too big or poorly positioned.(Photo by Sora Shimazaki/Pexels)

Doctors are warning ill-fitting menstrual cups could potentially lead to health concerns after the case of one woman who developed a rare case of temporary kidney problems.

Danish doctors quoted in the British Medical Journal advised there could be a rare, but serious consequence to using a menstrual cup. which is used to catch monthly blood flow, which isn’t correctly positioned or is of the wrong size.

In the case report, urologists Clara Maarup Prip and Lotte Kaasgaard Jakobsen from Aarhus University, state that menstrual cups are designed to fit at the edges of the vaginal wall, but if inserted incorrectly, they can compress the ureter, which could lead to a condition called “ureterohydronephrosis.”

In their report, a patient in her early 30s suffered from blood in her urine and pain in both her abdomen and her side for six months before her scans showed swelling in her kidney and ureter (the tube that carries urine to the bladder).

Imaging revealed a menstrual cup compressing the uterer’s opening at the juncture.

After the cup was safely removed, there was a complete regression of symptoms and the ureterohydronephrosis, they said.

At her one-month follow up, the patient continued to improve and felt no pain, and six months later, the patient admitted that she did not use the menstrual cup anymore, except during instances like visits to a swimming pool due to the fear of complications.

“Menstrual cups present a sustainable alternative to single-use devices, but complication rates are still sparsely described,” the study states.

What the evidence says

“A recent review of the literature on menstrual cup usage reported that possible complications include pain, vaginal wounds, allergic reactions, leakage, urinary incontinence, dislodgement of intrauterine devices, and infections,” according to the case report.

More serious complications found in other cases include toxic shock syndrome and effects on the upper urinary tract.

While there have been only a handful of case studies about menstrual cups causing pain in the ureter, and most incidents were reported to be easily managed, the sample size to test the theory that menstrual cups are indisputably safe is too small to conclude that.

There needs to be more awareness surrounding use of menstrual cups and choosing the right shape, size, and insertion method to side-step any complications, the report says.

“The increasing use of menstrual cups calls for more knowledge on complication rates to enlighten both users and clinicians.”