If you’re in your late 40s or early 50s, you may begin experiencing symptoms of perimenopause, the lead up to menopause. Menopause is marked by the absence of menstrual periods for a full year. Perimenopause can last for months or years as hormones change. The process of menopause typically takes place from age 40 to age 60, although the average age of menopause is 51, according to The Mayo Clinic. Premature menopause can occur before age 40.