Effectiveness of transcutaneous auricular vagus nerve stimulation in alleviating postpartum blues following cesarean delivery: A randomized double-blind controlled trial.

Postpartum blues (PPB) is considered a prodromal stage of postpartum depression. This randomized controlled trial evaluated the effectiveness of transcutaneous auricular vagus nerve stimulation (taVNS) in alleviating PPB following cesarean delivery. One hundred participants were randomly assigned to receive active (n = 50) or sham (n = 50) taVNS over 5 days, with outcomes monitored through three months postpartum. The primary outcome demonstrated a significantly smaller increase in visual analogue scale scores, reflecting PPB severity, after the mood induction procedure in the active group than in the sham group on postpartum day 5 (median difference, 4.13 cm; 95% CI, 3.39-4.93; mixed-effects model, p < 0.001). The taVNS also significantly improved general postpartum mood on day 5, as assessed by Profile of Mood States (mixed-effects model, p < 0.001) and Stein Maternity Blues Scale (p < 0.001). At 1 month postpartum, the proportion of participants with Edinburgh Postnatal Depression Scale scores ≥13 was lower in the active group than in the sham group (4% vs. 26%; p = 0.003). Active taVNS also lowered postoperative pain scores at 4, 12, 24, 48, and 72 h (all p < 0.001) and improved sleep quality (assessed by the Richards-Campbell Sleep Questionnaire) on postoperative days 1 to 4 (all p < 0.001). These findings indicated that a 5-day taVNS intervention mitigated PPB severity after cesarean delivery and were associated with improved general mood, lower rates of Edinburgh Postnatal Depression Scale scores ≥13 at 1 month postpartum, reduced acute postoperative pain, and improved sleep quality. Chinese Clinical Trial Registry (https://www.chictr.org.cn/indexEN.html), ChiCTR2500108903.