Perimenopause, which means "around menopause," refers to the 2 to 8 years of changing hormone levels and related symptoms that lead up to menopause. The most common sign of perimenopause is longer, often irregular menstrual cycles that are caused by hormonal ups and downs.

Most women start perimenopause between ages 39 and 51.⁸ Some women begin to notice menstrual changes and premenstrual syndrome (PMS) symptoms in their late 30s when hormones begin to fluctuate and fertility naturally declines. Other women don't notice perimenopausal changes until their late 40s.

Perimenopause is a time of unpredictability. Menstrual and hormone-related symptoms are different for every woman-some notice few or no changes, and others have severe symptoms that disrupt their sleep and daily lives. As during the teen years, irregular cycles can lead to heavy menstrual bleeding. Other common symptoms include mild to severe hot flashes, insomnia, cloudy thinking, headaches, heart palpitations, mood swings, irritability, depression, and anxiety. Some of these symptoms can also be related to aging and other life changes. See your health professional to discuss your symptoms and whether you want symptom treatment, as well as which therapies you can consider.

See a health professional for menstrual bleeding that lasts longer than 7 days or for cycles that are shorter than 21 days or longer than 35 days. For more information, see the topics Dysfunctional Uterine Bleeding and Menopause and Perimenopause.