A Clinical Study for Magnetic Stimulation of the Posterior Tibial Nerve in Overactive Bladder

Inclusion Criteria: * Women \>18 years of age * A score of \> 4 on the OAB-q short form for urgency (question 1) * Average urinary frequency \> 10 times in one 24 hour day based on a 3-day voiding diary * Self-reported bladder symptoms present \> 3 months * Self-reported failed conservative care (e.g., dietary restriction, fluid restriction, bladder training, behavioral modification, pelvic muscle training, biofeedback, etc.) or use of antimuscarinics. * Off all anti-muscarinics for at least 2 weeks prior to enrollment * Capable of giving informed consent * Ambulatory and able to use a toilet independently, without difficulty * Capable and willing to follow all study-related procedures Exclusion Criteria: * The patient is pregnant or intends to become pregnant during the course of the study. (Patients becoming pregnant during the course of the study will immediately be terminated from the study.) * The patient has an active urinary tract infection. * Neurogenic bladder * Botox use in bladder or pelvic floor muscles in the past year * Pacemakers or implantable defibrillators * Primary complaint of stress urinary incontinence * Current vaginal infection * Current use of InterStim * Current use of Bion * Current use of TENS in the pelvic region, back or leg * Previously been treated with PTNS * Use of investigational drug/device therapy within the past 4 weeks * Participating or have participated within the past 4 weeks in any clinical investigation involving or impacting gynecologic, urinary or renal function * Deemed unsuitable for enrollment in study by the investigators based on subjects' history or physical examination * The patient has metal implant from surgery or a metallic foreign body in either leg below (distal to) the knee (or permanent metallic tattoo \<30cm from left ankle). * The patient has chronic constipation (less than two (2) bowel movements per week) * The patient has history of gastric or urinary retention * The patient has uncontrolled diabetes * Subjects with nerve damage, injury or surgery that would impact either tibial nerve or pelvic floor function * The patient is unable or unwilling to sign informed consent * The patient is currently on pharmacologic treatment that could affect bladder function * Known Cystocele \>/= to Grade 3 that has not been reduced by treatment (surgery or pessary)