Scientists Think They’ve Figured Out What Causes Severe PMS

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If premenstrual syndrome is a little annoying, then premenstrual dysphoric disorder is true hell on earth. PMDD affects 2 to 5 percent of reproductive-age women with symptoms that mimic depression and anxiety, like debilitating sadness, hopelessness, and irritability in addition to physical issues like bloating and fatigue. But, frustratingly, women with PMDD have the same hormone levels of women with the more common PMS even though they react differently.

Researchers at the National Institutes of Health wanted to see if there was something different going on at a cellular level. For a study published in the journal Molecular Psychiatry, they suppressed then added back the hormones estrogen and progesterone in women with PMDD and a control group of women. When they “turned off” these hormones, the women with PMDD saw their symptoms disappear only to re-emerge when the hormones were added back. The control group had no change. This confirmed that women with PMDD are more sensitive to the hormones.

Then they looked at white blood cells from both groups since they express many of the same genes as brain cells. The researchers found a large gene complex where genes expressed differently in women with PMDD compared to the control group. Specifically, the differences were found in a complex that determines how cells respond to the environment, including sex hormones and stressors. Some of the genes were over-expressed and others were under-expressed in PMDD patients; exposure to estrogen and progesterone also altered their gene expression. This dysregulated cellular response could be why women with PMDD are so sensitive to the hormones.

As lead researcher David Goldman, M.D., said in a release, “This is a big moment for women’s health, because it establishes that women with PMDD have an intrinsic difference in their molecular apparatus for response to sex hormones — not just emotional behaviors they should be able to voluntarily control.” They’re also hopeful that the finding will lead to improved treatments for PMDD but that will take many more studies.

Could This Be the Cause of Severe PMS?