To help distinguish the two, chart your symptoms through two menstrual cycles to see if they appear only in the week before menstruation and go away a day or two after bleeding begins. If a clear and persistent pattern emerges, it’s likely that changing hormone levels are to blame. If a clear pattern doesn’t emerge, depression may be the culprit.

The Effect of Hormones

Premenstrual dysphoric disorder is a severe form of PMS that occurs in 2% to 10% of menstruating women. It can cause symptoms similar to a major depressive episode in women who are unusually sensitive to the changing hormone levels of the menstrual cycle. Some of that sensitivity may be due to interactions between female hormones and neurotransmitters that regulate mood and arousal.

Whether PMS, premenstrual dysphoric disorder, or depression is at the root of your symptoms, it’s important to talk to your doctor about the fluctuations in your mood and how best to treat them.

Researchers are also investigating whether hormones play a role in depression around the time of menopause. Some women report feeling depressed during perimenopause, a time of transition that occurs in the months or years before menstruation stops. It’s commonly believed that declining levels of estrogen are to blame, although this has not been proved scientifically. When estrogen is given to treat depression, the results have been mixed. For now, estrogen’s role in depression during perimenopause remains controversial.

The Role of Genetics

There is evidence to suggest that genes play a role, too. Researchers have identified certain genetic mutations that are linked to severe depression - some of which are found only in women. In one of these cases, the mutation is in a gene that controls female hormone regulation. These biological differences could account for some of the difference in the rates of depression between men and women.

References
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