Women do not synchronize their menstrual cycles

  title={Women do not synchronize their menstrual cycles},
  author={Zhengwei Yang and Jeffrey C. Schank},
  journal={Human Nature},
It is widely believed that women who live together or who are close friends synchronize their menstrual cycles. We reexamined this phenomenon in two ways. First, we collected data on menstrual cycles from 186 Chinese women living in dorms for over a year. We found that women living in groups did not synchronize their cycles. Second, we reviewed the first study reporting menstrual synchrony. We found that group synchrony in that study was at the level of chance. We then show that cycle… 
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  • J. Schank
  • Medicine, Psychology
    Journal of comparative psychology
  • 2001
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  • Psychology, Medicine
    American journal of human biology : the official journal of the Human Biology Council
  • 1993
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