Why bladder symptoms often worsen before and during menstruation

In this video, Aleece Fosnight, MSPAS, PA-C, CSC-S, CSE, IF, MSCP, HAES, founder of the Fosnight Center for Sexual Health and a medical advisor for Aeroflow Urology, explains that cyclical urinary symptoms—such as urgency, frequency, and stress incontinence—commonly worsen in the luteal phase and around menstruation due to predictable hormonal and inflammatory shifts.

Progesterone plays a central role during the luteal phase, when its levels peak. Because progesterone relaxes smooth muscle, it can reduce tone in both the detrusor muscle and the urethral sphincter. For some patients, this leads to inadequate urethral closure, contributing to stress urinary incontinence, increased urgency, and greater bladder sensitivity to urine.

At the same time, estrogen levels decline. Estrogen is a key supportive hormone for the genitourinary system, helping maintain urethral mucosal thickness, vascularity, and normal bladder sensation. As estrogen withdraws before menstruation, the urethra and bladder lose this support, resulting in heightened bladder sensitivity, lower thresholds for discomfort, and more irritative voiding symptoms.

Inflammation further compounds these effects. Menstruation triggers increases in prostaglandins and inflammatory cytokines, both systemically and locally. These substances can irritate the bladder, increase detrusor activity, reduce functional bladder capacity, and even exacerbate pelvic pain. Fosnight notes that patients may assume this discomfort originates from the uterus, when in fact the bladder is often involved.

Hormonal changes also influence fluid balance and bloating, increasing pressure within the pelvis. Because pelvic space is limited, this redistribution can compress or irritate the bladder and provoke pelvic floor overactivity, further worsening urgency and frequency. Fosnight refers to this as “bladder bystander syndrome,” emphasizing that the bladder is often affected by surrounding changes rather than being the primary problem.

Finally, hormones modulate the nervous system. During the premenstrual phase, sensory hypersensitivity and altered autonomic regulation mean the brain interprets bladder signals differently. Symptoms may intensify even without increased bladder contractions, reflecting heightened perception rather than structural dysfunction alone.