Caspian Journal of

BACKGROUND AND OBJECTIVE: The menstrual synchrony is a process in which the onset of a menstrual cycle is very close in people living together. The question is arisen whether menstrual synchrony can be affected by common environmental and social factors, especially food, similar life patterns and common stress periods. The aim of this study was to investigate the relationship between menstrual synchrony and common activities.
METHODS: This descriptive study was conducted on 182 female students residing in dormitory of Islamic Azad University of Tonekabon-Iran in 2017-2018. In this study, sampling method was available and relevant information was collected using a researcher-made questionnaire on a monthly basis during 6 consecutive months from November 2017 to May 2018. This questionnaire included 19 items. Face and content validity of the questionnaire was assessed and its reliability was 0.729 based on Cronbach's alpha coefficient. The data were analyzed via descriptive statistics including mean, standard deviation and frequency as well as inferential statistics such as Spearman and Friedman’s correlation coefficient and T-test using SPSS 22.
FINDINGS: According to the findings, there was a significant correlation between the activities of student roommates and menstrual synchrony in three consecutive months. In fact, the significant relationship was observed during a short time when the studied groups were influenced by similar patterns. However, no significant relationship was found with the starting of holidays and disruption of ongoing factors of common activities.
CONCLUSION: The results showed that there was a significant relationship between menstrual synchrony and common activities stated in questionnaire during three consecutive months. It means that the more common activities (especially consumption of food, similar life patterns and so on) are, the more menstrual synchrony is observed. The role of common activities is crucial in menstrual synchrony. Common activities are even more important than living together, hence; further studies should be performed in this field.