The effect of Polyvagal Theory-based vagus nerve stimulation on labor pain, anxiety, oxytocin, cortisol levels, labor duration, and birth perception

This study was conducted to determine the effects of vagus nerve stimulation based on Polyvagal Theory on labor pain, anxiety, oxytocin and cortisol levels, labor duration, and maternal birth perception in women during childbirth. Designed as a randomized controlled experimental study, it was carried out between June 1, 2024 and April 30, 2025 at Adana Seyhan Government Hospital with 48 primiparous women who had vaginal deliveries. The study was conducted with one intervention group and one control group. The intervention aimed to stimulate the vagus nerve through natural methods. A video-guided application protocol was developed for this purpose. Participants performed the application while watching the video at three different cervical dilatation levels: 3–4 cm, 5–6 cm, and 8–9 cm. Data were collected using the Personal Information Form, Visual Analog Scale (VAS), Facial Anxiety Scale (FAS), State Anxiety Inventory (STAI-I), Hormone Monitoring Form, Labor Process Monitoring Form, and the Maternal Perception of Birth Scale (MPBS). All measurements, except for the MPBS, were taken at the three different dilatation stages. Ethical approval, institutional permission, and written informed consent from participants were obtained for the study. Data were analyzed using SPSS version 29, with a statistical significance level set at p<0.05. No significant differences were found between the groups in terms of descriptive variables, VAS, FAS, STAI-I, oxytocin, and cortisol mean scores before the intervention (p>0.05). Post-intervention comparisons between the groups revealed statistically significant differences in all measurement times for VAS, FAS, STAI-I, oxytocin, cortisol, duration of labor, and MPBS total scores (p<0.05). Within-group comparisons also showed statistically significant differences in VAS, FAS, and STAI-I scores, as well as in oxytocin and cortisol levels (p<0.05). In the intervention group, compared to pre-tests measurements, there were significant improvements in VAS, FAS, and STAI-I scores, a significant decrease in cortisol levels, and a significant increase in oxytocin levels (p<0.05). These findings suggest that video-guided vagus nerve stimulation may be effective in reducing labor pain and anxiety at different stages of cervical dilatation, increasing oxytocin levels, decreasing cortisol levels, shortening the duration of labor, and supporting a more positive childbirth experience.