Some researchers – and surely many women – have suspected that stress can exacerbate symptoms of PMS. Some of the most common symptoms of premenstrual syndrome are anger, anxiety, depression, mood swings and decreased concentration – all things that clearly could be made worse by stress.
At least 10 studies have found an association between stress and PMS symptoms, but none was able to tell whether stress made symptoms worse – or if severe PMS caused women to feel stressed out. To answer that question, researchers from the National Institute of Child Health and Human Development and colleagues tracked 259 women over two-and-a-half menstrual cycles to see how stress before a cycle affected PMS.
It turned out that women who had high scores on the Perceived Stress Scale in one month were much more likely to have moderate or severe psychological PMS symptoms in the next month, compared to low-stress women. For instance, high-stress women were twice as likely to experience anger, short temper, anxiety and irritability, and three times more likely to report sadness, depression or crying spells.
The most convincing evidence that stress is a cause, not an effect, of PMS came from the subset of women who were high-stress before one cycle and low-stress before the other.