Using a menstrual cup is generally positive, yet many users encounter a frustrating side effect: difficulty starting or maintaining a urine stream, or the persistent feeling that the bladder has not completely emptied. This common problem stems from the mechanical nature of how the cup sits inside the body. The core issue is temporary pressure or obstruction on the urinary system, which causes a slow flow or an uncomfortable sense of incomplete voiding.
Understanding the Anatomy of the Pelvic Region
A menstrual cup can interfere with urination due to the very close arrangement of organs in the female pelvic area. The vaginal canal, where the cup is placed, sits directly behind the urethra, the tube that carries urine from the bladder out of the body. The urethra is a relatively thin, collapsible structure running parallel to the front wall of the vagina.
The bladder, which stores urine, is positioned just above and in front of the vagina. When a menstrual cup is inserted and opens to form its seal, it takes up space within the vaginal canal. This expansion can push forward against the adjacent, soft tissues of the urethra or the neck of the bladder.
If the cup is too large in diameter, too firm, or positioned too low, the pressure it exerts can partially compress the urethra. This pressure acts like a kink in a garden hose, restricting the free flow of urine and leading to the slow stream or the sensation of needing to push to urinate. The pressure can also stimulate the bladder lining, causing a false signal of fullness or urgency, even when the bladder is not full.
Simple Adjustments to Relieve Pressure
Since the issue is mechanical pressure, the solution often involves minor changes to the cup or its placement. One of the simplest adjustments is to ensure the cup is positioned correctly, aiming it slightly toward the back of the vaginal canal during insertion. This small tilt can move the cup away from the sensitive anterior wall that houses the urethra.
If repositioning does not help, the firmness and size of the cup should be considered. A cup made from a softer silicone material will exert less radial pressure against the vaginal walls and adjacent structures than a much firmer cup. Similarly, switching to a cup with a slightly smaller diameter can reduce the overall space it occupies, minimizing the chance of urethral compression.
The strong suction seal created by the cup can contribute to pressure on the surrounding tissues. Gently breaking the seal by pressing on the side of the cup before attempting to urinate may alleviate the pressure enough for a free flow. Adjusting your posture on the toilet, such as leaning slightly forward or backward, can momentarily change the angle of the pelvic organs, which may relieve the temporary obstruction.
When Difficulty Urinating Signals a Serious Issue
While mild difficulty urinating is usually a minor inconvenience, certain symptoms warrant immediate medical attention. The complete inability to pass any urine, known as acute urinary retention, requires prompt removal of the cup and a visit to an urgent care facility or emergency room. Prolonged retention causes significant discomfort and places harmful pressure on the kidneys.
Seek professional medical advice if you notice blood in your urine, experience severe pain in your lower abdomen or flank area, or if you develop symptoms consistent with a urinary tract infection (UTI). These symptoms include a persistent burning sensation during urination, cloudy or foul-smelling urine, or fever. In rare documented cases, a severely misplaced cup has been linked to a blockage of the ureter, the tube carrying urine from the kidney, which can cause a swollen kidney, or hydronephrosis. If you experience these more serious signs, discontinue cup use immediately and consult a healthcare provider.