Menopause marks an important life stage for many women. During this time, her menstrual periods stop occurring, and she can no longer become pregnant. In the years leading up to menopause, a woman undergoes a transitional stage known as perimenopause. To better understand the body’s important transition, here is a guide to the symptoms of menopause.

Menopause technically begins once periods have completely ceased for one year. While the average age for the onset of menopause is 51, women can stop menstruating at almost any adult age. Some women may have few to zero signs that indicate impending menopause, while others will experience a wide range of symptoms. While these symptoms are a natural part of a biological process and require no cure, treatment is available to help alleviate any ongoing discomfort.

Irregular periods
A woman’s period may start to appear off schedule, arriving late or early and lasting for shorter or longer stretches of time. The period may also be lighter or heavier than usual. Women should note that period cessation does not always signal menopause. An irregular period or none at all may be a sign of another underlying health condition, such as pregnancy.

Hot flashes
One of the most common symptoms of menopause, hot flashes refer to sudden sensations of body heat. Women may see red blotches on their skin, or they might start sweating and shivering. Night sweats form hot flashes can also cause difficulty sleeping. Hot flashes are caused by the decreased amount of estrogen, which confuses the hypothalamus–an important part of the brain responsible for regulating body temperature. According to the North American Menopause Society, hot flashes affect as many as 75 percent of menopausal women in the United States.

Decreased vaginal health
Estrogen plays a large role in the vagina’s overall health. The hormone helps protect the urinary tract from infection, and lowered levels of estrogen can cause the vaginal walls to become drier and thinner. Women entering menopause may be more susceptible to urinary tract infections.

Mood swings
Estrogen and progesterone also contribute to mood regulation, and hormonal shifts can lead to mood changes. Women may experience feelings of crankiness, crying spells or severe mood swings from extreme euphoria to tearful sadness. Menopause can also heighten levels of stress and anxiety.

Cognitive changes
Many women have difficulty focusing and issues with remembering details as their menopause advances — symptoms that also occur as a natural part of aging. Many women may fear this is a sign of Alzheimer’s disease, but short-term memory problems can arise for a number of reasons, including menopause or mood disorders.

Shifts in sex drive
For some women, menopause can introduce a sexual resurgence and greatly increase the desire for sex. Others feel a diminished sex drive, due in part to aging as well as decreased hormones during menopause. Lifestyle changes may help increase a woman’s sex drive. Regular exercise and a healthy diet can contribute to overall health, which is a huge factor for sex. For more information on menopause, including its effects on sex drive, visit the U.S. Department of Health.