A novel transcutaneous auricular neurostimulation electrode configuration for treatment of heavy menstrual bleeding: an open-label trial.

BACKGROUND: Electrical stimulation of the cervical vagus nerve reduces traumatic blood loss in models of soft tissue injury. This pathway, termed the neural tourniquet, can be accessed with a transcutaneous auricular neurostimulation (tAN) targeting vagus and trigeminal nerve branches on and around the ear. The cymba concha is the most targeted dermatome to activate the auricular branch of the vagus nerve (ABVN); however due to variable ear anatomy, participants can report electrode discomfort leading to reduced treatment compliance and device usability. This study examined a novel electrode configuration to improve hemostasis during menstruation and device usability. METHODS: This open-label pilot trial (NCT06814028) sought to determine whether the use of tAN reduced menstrual blood loss in women with heavy menstrual bleeding (HMB). The device included a novel electrode configuration through which the auricular branch of the vagus nerve (ABVN) was targeted posterior to the auricle, near the mastoid process. Participants with a history of heavy menstrual bleeding gave informed consent to participate in an IRB-approved, decentralized clinical trial. Participants were followed for three consecutive menstrual cycles, during which estimated daily blood loss using a validated pictorial blood loss assessment chart (PBAC) and menstrual symptoms were recorded at the end of each menstruation. During the first menstruation, baseline PBAC and menstrual symptom scores were measured without the use of tAN. During the second menstruation, participants self-administered two 1-h sessions of tAN daily throughout menstruation; during the third menstruation, participants self-administered one 2-h session of tAN daily throughout menstruation. The PBAC was also used to calculate the duration of each menstruation, defined by the use of menstrual products. Student’s paired T-test was used to compare mean outcome scores to baseline. RESULTS: Use of the novel electrode design to deliver tAN was associated with lower PBAC scores and reduced duration of menstruation as compared with baseline. Notably, device usability surveys of participants revealed high device satisfaction scores, including comfort of the novel electrode configuration. CONCLUSIONS: These pilot results suggest that stimulating the ABVN posterior to the auricle is effective, safe and feasible for reducing menstrual blood loss in women with HMB.