There is no clear evidence that women get more moody in the pre-menstrual phase of their cycles, researchers report. The team analyzed 41 research studies that tracked women’s daily moods through their menstrual cycles. Their findings—which showed no clear evidence that pre-menstrual syndrome (PMS) exists—are published online now in the journal Gender Medicine. “There is so much cultural baggage around women’s menstrual cycles, and entire industries built around the idea that women are moody, irrational—even unstable—in the phase leading up to menstruation,” says Gillian Einstein, associate professor of psychology and public health at the University of Toronto.