PMDD or Premenstrual Dysphoric Disorder is a condition which affects around 5.5% of women and AFAB individuals of reproductive age. PMDD causes severe emotional symptoms, like depression, anxiety, mood swings, anger, or even thoughts of suicide. Some people also have physical symptoms such as fatigue, bloating and sleep issues.

These symptoms ONLY happen the 1-2 weeks before their menstrual period starts. So the symptoms look like a severe mood disorder, but they are only present in that premenstrual window. 

We know that PMDD is caused by an abnormal brain reaction to normal changes in hormones across the cycle. HORMONE LEVELS ARE NORMAL IN PMDD, but the brain cannot adapt to the normal monthly changes for an unknown reason.  

PMDD is a suspected genetic disorder with symptoms often worsening over time and around reproductive events including menarche, ovulation, pregnancy, birth, miscarriage, and perimenopause. 

In 2016, researchers at the National Institutes of Health (NIH) found that women with PMDD are more sensitive to the effects of sex hormones estrogen and progesterone, due to a molecular mechanism in their genes. Researchers compared white blood cells in women with PMDD and those without, and confirmed that women with PMDD have an altered response to sex hormones at the cellular level.

Updated 16 November, 2019 by Tory Eisenlohr-Moul, PhD