Effect of Peripartum 40 Hz Audiovisual Stimulation on Postpartum Depression in Women Undergoing Elective Cesarean Section: A Randomized Clinical Trial

Postpartum depression (PPD) is a common mental health condition affecting 10%-30% of new mothers, with serious consequences for both mother and child. Effective prevention is limited by barriers to psychological or pharmacological treatments. This study evaluates whether short-term 40 Hz light and sound stimulation during and immediately after elective cesarean section can reduce PPD risk. The intervention group receives three 30-minute sessions of combined 40 Hz flashing light and pulsed sound (starting after baby delivery, then at 24 and 48 hours postpartum). The control group receives identical non-flickering light and white noise as placebo.The main outcome is the Edinburgh Postnatal Depression Scale score at 42 days postpartum. Secondary outcomes include depression rates, insomnia severity, and anxiety levels.Participants are women aged ≥18 years with single full-term pregnancy scheduled for elective cesarean section. Exclusion criteria include psychiatric disorders, epilepsy, or eye conditions affecting light sensitivity. If effective, this non-invasive, drug-free intervention could provide a safe and accessible PPD prevention strategy during routine cesarean delivery.