A study of parasympathetic autonomic function in different phases of the menstrual cycle among young adult females

Background: The sex hormones, estrogen, and progesterone, as well as the gonadotropins, luteinizing hormone, and follicle-stimulating hormone produced from the anterior pituitary, govern the three stages of the menstrual cycle: menstrual, follicular, and luteal. Hormone fluctuations cause changes in autonomic function. There have been relatively few studies that show autonomic function modification throughout various periods of the menstrual cycle. Aim and Objectives: The current study was undertaken to investigate the difference in mean parasympathetic autonomic characteristics between the proliferative and secretory stages of the menstrual cycle. Materials and Methods: A total of 120 healthy young adult female volunteers were recruited among Kalinga Institute of Medical Sciences, Kalinga Institute of Nursing Sciences, and Kalinga Institute of Dental Sciences students. The study eliminated 20 students who were in the bleeding phase of their cycle. The electrocardiogram was captured, and parasympathetic parameters were determined using the fully automated CANWin instrument in the Department of Physiology. The data of the abovementioned parameters were compiled, tabulated, and entered into Microsoft Excel 2013 and statistically analyzed using STATA software 15.1. Results: The subjects' mean ages, heights, and weights were 18.9 ± 0.70 years, 156.6 ± 5.25 cm, and 53.7 ± 8.63 kg, respectively. The mean resting heart rate in the secretory phase was substantially greater than in the proliferative phase, indicating sympathetic dominance. The 30:15 ratio between proliferative and secretory stages. The mean E: I ratio calculated from the slow deep breathing maneuver reveals a statistically significant difference between the proliferative and secretory phases. Conclusion: During the secretory phase, there is a considerable rise in parasympathetic activity among the individuals in the current study. Changes in parasympathetic activity throughout the follicular and secretory stages of the menstrual cycle may be caused by fluctuations in estrogen and progesterone levels.