MTHFR is a gene that provides the body with instructions for making a certain enzyme called methylenetetrahydrofolate reductase (MTHFR).

There are two predominant MTHFR polymorphisms, 677C>T and 1298A>C. In the general population, 60–70% of individuals will have at least one of these variants, yet only 5.5% of women and AFAB individuals will experience PMDD.

These numbers would not suggest that MTHFR causes PMDD.

Indeed, there is no evidence to suggest a causal connection (that is, that having one leads to the other) between MTHFR abnormalities and PMDD, but there is also very little research in this area.

In fact, there are no published scientific studies assessing MTHFR genotype in PMDD.

Dr. Liisa Hantsoo - Clinical Psychologist & Assistant Professor at The Johns Hopkins University School of Medicine

Added 20th June 2023