A zap to the ear for better sleep during pregnancy? a trial puts it to the test

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Females aged 18-35 years, gestational age 20-34 weeks. Stable physical condition confirmed by routine laboratory tests (complete blood count, liver function, renal function, thyroid-stimulating hormone), urine toxicology screening, and electrocardiogram (ECG) at screening. Fetal ultrasound and fetal heart rate monitoring performed and assessed by an obstetrician-gynecologist prior to enrollment. Insomnia symptoms meeting all of the following criteria: At least one of: (a) sleep onset latency \> 30 minutes; (b) nocturnal awakenings ≥ 2 times/night; (c) total sleep time \< 6 hours; (d) accompanied by daytime dysfunction. Symptoms occur despite adequate opportunity and appropriate circumstances for sleep. At least one sleep-related daytime impairment: fatigue/malaise; impaired attention/memory; decreased academic/occupational/social functioning; mood disturbances/irritability; daytime sleepiness; reduced interest/energy; increased errors during work or driving; tension/headache/dizziness or other somatic symptoms related to sleep deficiency. Symptoms persisted for ≥ 2 weeks. Confirmed eligible for enrollment by both an obstetrician and a neurologist. Willing and able to provide signed informed consent. Exclusion Criteria: * History of psychiatric disorders prior to pregnancy. History of psychoactive substance abuse. Prior exposure to taVNS (transcutaneous auricular vagus nerve stimulation) treatment. Cardiac arrhythmia, particularly bradycardia. Currently receiving hypnotic medications or other insomnia treatments. Known fetal abnormalities (e.g., intrauterine growth restriction, congenital malformations, or cardiac rhythm abnormalities detected on fetal ultrasound). History of adverse pregnancy outcomes or current pregnancy with known obstetric complications (e.g., gestational hypertension, gestational diabetes, or abnormal prenatal examination results). Deemed unsuitable for enrollment following assessment by either the obstetrician or neurologist.