(Reader’s Digest) — If you find yourself feeling blue during menopause, there may be a really good reason why.

Hormones can trigger a roller coaster of emotions in women. From the severe mood swings of premenstrual dysphoric disorder (PMDD) to an PMS-driven increase in anxiety, hormones can wreak havoc on a woman’s emotional stability. Thanks to the latest research provided in a study, we’re now a little closer to understanding why certain women seem to experience depression at the onset of menopause and post-menopause while others seemingly skate through without trouble.

A new study published in Menopause, the journal of The North American Menopause Society (NAMS), reveals that women with a longer lifetime exposure to a certain type of estrogen have a much lower risk of depression at menopause, reports Science Daily. Researchers tracked estrogen levels in more than 1,300 regularly menstruating premenopausal women. In particular, they focused on estradiol, a form of estrogen involved with the production and availability of serotonin, which is a key neurotransmitter in depression. Women who started menstruating earlier in life—thus increasing their exposure to estradiol—or who were on birth control for long periods had much lower risk of depression.