Abstract
Purpose
This study aimed to examine the changes in the autonomic nerve activity by RR-interval variability and the feeling of a relaxation by using a relaxation scale during early postpartum days, and investigated the related factors.
Method
Scores of autonomic nervous system activity and subjective relaxation of 127 postpartum women were collected 1-3days after delivery. Autonomic nervous system activity was assessed using the heart rate, RR-interval variability, low frequency/high frequency (LF/HF) ratio, and HF, all of which were measured using LRR-03 (GMS). The HF and LF/HF ratio was used as an index of parasympathetic and sympathetic nervous activity respectively. The data collected were analyzed using a growth curve model.
Result
The HF value and the LF/HF ratio was the highest on the first postpartum day and decreased on the second and third postpartum day. The differences in HF, LF/HF ratio and relaxation scores between the first and third postpartum days were insignificant. The relaxation scores on the second and third postpartum days were found to be influenced by the relaxation score on the first postpartum day. The HF and relaxation scores were related to the experience of childbirth and the age of the mother. The relaxation score increased with increase in the frequency of delivery, and the HF value was influenced by the age of the mother. Moreover, the HF was high when the relaxation score on the first postpartum day was high, and the HF value progressively decreased on daily basis.
Conclusion
The HF and LF/HF ratio were higher on the first postpartum day than on the second and third postpartum days. The autonomic nerve activity was thought to be unstable on the first postpartum day. This study suggests the importance of realizing the psychological state of the first postpartum day to provide timely postpartum care depending on the condition of the mother.
