Right Prefrontal Autonomic Mapping in Recurrent Pregnancy Loss With Comorbid Anxiety

Recurrent pregnancy loss is often accompanied by substantial anxiety and may also be associated with autonomic imbalance and increased long-term cardiovascular vulnerability. The present proof-of-concept rTMS-ECG parameter-finding trial will examine whether high-intensity, low-frequency, periodic repetitive transcranial magnetic stimulation (rTMS) delivered over the right dorsolateral prefrontal cortex can induce detectable acute cardiac autonomic responses in women with recurrent pregnancy loss and comorbid anxiety disorders. A total of 55 women will be enrolled. During a single experimental session, each participant will undergo a stimulation-intensity sweep protocol with six consecutive stimulation cycles at 100%, 110%, 120%, 130%, 140%, and 150% of resting motor threshold. Each cycle will consist of 40 seconds of 1 Hz stimulation followed by a 20-second rest interval, while electrocardiography will be recorded continuously throughout the procedure. The study will evaluate baseline-corrected heart-rate change, wavelet-derived power near the stimulation-cycle frequency, and the rTMS-induced cardiac coupling index across intensity conditions. The goal is to identify the candidate stimulation intensity that produces the most detectable and physiologically consistent acute cardiac autonomic response for transfer to subsequent NEURO-CARD-rTMS studies.