An ill-fitting menstrual cup caused a kidney infection in a woman by blocking her urine flow, leading to symptoms such as blood in her urine and pelvic pain. Proper cup size and positioning are crucial to avoid upper urinary tract issues, and clinical advice on cup usage is recommended to prevent complications. An ill-fitting menstrual cup caused a kidney infection in a woman by blocking her urine flow, leading to symptoms such as blood in her urine and pelvic pain. Proper cup size and positioning are crucial to avoid upper urinary tract issues, and clinical advice on cup usage is recommended to prevent complications. Health and Fitness, Health Tips, Exercises & Workout Tips, Diet & Wellness | Times of India Lifestyle