Dr Clara Maarup Prip, a urologist and gynaecologist at Aarhus University Hospital, Denmark, documented an unusual case of kidney swelling caused by a menstrual cup compressing the ureter. Published as “Ureterohydronephrosis due to a menstrual cup in BMJ Case Reports,” the paper spread quickly after it was press-released by the BMJ Group media relations team, sparking widespread discussion on safe cup use and symptom awareness.