Comparative study of time and frequency domain analysis of heart rate variability in different phases of menstrual cycle

Objective HRV analysis has gained much importance in recent years, as a technique employed to explore the activity of autonomic nervous system (ANS), and as an important early marker for identifying different pathological conditions. Autonomic nervous activities fluctuate during the menstrual cycle. The aim of the present study was to compare and evaluate, the changes in the ANS activity measured by the time and frequency domain analysis during different phases of menstrual cycle. Methods The subjects consisted of 54 healthy female students aged 18 ~ 25 years who had regular menstrual cycles. The electrocardiogram (ECG) recordings were taken during the different phases of the menstrual cycle. Heart rate variability (HRV) was analyzed by means of time and frequency domain analysis using appropriate software. Results A non significant change was observed in the time do main analysis during the different phases. In the frequency domain analysis, the low frequency component (LF) showed a significant increase and the high frequency component (HF) showed a significant decrease in the luteal phase when compared to follicular and menstrual phase. This study provides findings that the luteal phase of the menstrual cycle was associated with a greater increase in the LF component and a greater decrease in the HF component, resulting in a higher LF/HF ratio. Conclusion The power spectral analysis of the HRV namely the frequency domain reflects the activity of the autonomic nervous system in a larger way as compared to the time domain analysis.