European Journal of Cardiovascular Medicine

Background: During menstrual cycle the females undergo continuous variations in serum concentrations of female sex hormones. Moreover, the females in medical colleges struggle with lot of problems such as lifestyle, regular clinical duties and handling patients which create huge stress and affect their reproductive life. The oscillations in the hormonal levels found in different phases of menstrual cyclecause fluctuations in some of the physiological parameters like Peak expiratory flow rate (PEFR) which assess pulmonary function and muscle strength. Aims and objectives: This study aims to study the variation of PEFR, muscle strength and work done in different phases of menstrual cycle in medical students. Materials and methods: A total of 100 MBBS female students with regular menstrual cycle participated in the study. Participants were studied for 2 consecutive cycles in 3 phases of menstrual cycle. PEFR, work done and muscle strength were tested during each phase. Peak expiratory flow meter was used to measure PEFR. Muscle strength was measured using handgrip dynamometer and work done was obtained from Mosso’s ergograph. Data were statistically analyzed using repeated measures ANOVA and paired t- test. P<0.05 was considered significant. Results:  PEFR was significantly higher in the luteal phase of menstrual cycle as compared to the menstrual and follicular phase as observed in other studies in general population. Muscle strength and work done were observed higher in follicular phase as compared to menstrual and luteal phase, however the difference was not statistically significant. Conclusion:The observed improved PEFR in luteal phase may be due tohyperventilation and bronchodilation effect of progesterone on pulmonary function. Muscle strength and work done does not show significant variations during different phases of menstrual cycle.