While you might think everyone gets a little irritable (OK, bitchy) during menopause, research proves that menopause doesn't cause a major mood problem in most midlife women. While women are twice as likely to suffer from depression as men, you're more likely to be diagnosed with depression before the age of 44 than when you're older. In fact, here's a surprise: the majority of women between 45 and 55 describe these years as the best of their lives.

But there's no denying that some of us are in for a bumpy ride, even clinical depression, maybe for the first time in our lives. Some women's moods are much more sensitive to hormonal changes than others, and they have a particularly rough time during perimenopause, when zig-zagging hormones are the rule. Hot flashes, night sweats and insomnia have been known to leave more than a few women moody and depressed. Side effects of medications or an undiagnosed thyroid problem could be the culprits. Or maybe the stresses that many of us are dealing with at midlife are just too much--work, coping with kids or teenagers, caring for elderly parents.

If you have a range of bothersome symptoms (irritability, trouble concentrating or making decisions, headaches, sleep or appetite changes, or just not enjoying your usual activities anymore), you don't have to wait until you have a full-blown case of anxiety or depression to take action. Increasing your exercise level, exposing yourself to more light and even making a concerted effort to be happy can make a difference. If that's not enough, talk to your doctor about whether a short course of low-dose antidepressants or talk therapy (or both) could help you get back on track. Some of these drugs (Prozac, Paxil and Effexor) have the side benefit of reducing the frequency and intensity of hot flashes, but they can also cause other side effects.

If you've got a history of mood problems, take the initiative and talk to your doctor early about ways to monitor and manage your mood. A minority of women experience severe mood swings closely tied to hormonal changes. These women may be at higher risk for mood fluctuations during perimenopause and should consult their doctor about whether a short course of hormone therapy or a combination of hormones and antidepressants could be the most effective treatment.

Don't ignore these problems. Depressive symptoms put you at higher risk for many long-term health problems, including cardiovascular disease, dementia, stroke and osteoporosis.