The physical changes that usher in menopause may begin as early as your 30s or as late as your 50s. Symptoms may include missed periods, hot flashes, and weight gain.

Menopause is characterized by a natural decline in fertility. As you age, your ovaries produce less of certain hormones. Menstruation becomes irregular and eventually stops.

You reach menopause after you experience 12 consecutive months without a menstrual period. The time before this stage is known as perimenopause, and the time after this stage is known as postmenopause.

This transition usually takes about 7 years from beginning to end, but it can last as long as 14 years for some.

It’s important to remember that menopause symptoms are not linear or wholly defined by age.

You may experience certain symptoms earlier or later than expected or notice the same symptoms come and go over an extended time.

A couple of missed periods when you’re 40 might make you think you’re pregnant, but it’s also possible to begin menopause around this age.

Approximately 5% of people experience early menopause, which occurs between ages 40–45. Natural menopause that occurs before age 40, which is known as premature menopause, is less common.

Early or premature menopause is primarily characterized by unexpected menstrual irregularities. This includes:

  • missing more than two or three consecutive menstrual periods
  • a shorter or longer menstrual cycle
  • heavier or lighter menstrual flow

Going into menopause early could prevent you from conceiving if you’ve been waiting. You may want to consider options like freezing your remaining eggs or using donor eggs to conceive.

Perimenopause typically begins in your late 40s. You’ll likely still get a period during this time, but your menstrual cycles will become more erratic over time.

You may notice more missed periods during the last year or two of perimenopause. The periods you do get could be heavier or lighter than usual.

Physical symptoms may include:

Mental and emotional symptoms may include:

It’s more difficult to get pregnant during perimenopause, but it isn’t impossible. If you don’t want to conceive, continue to use contraception during this time.

By your early 50s, you may be in menopause or making the final transition into this stage of life. You may continue to experience symptoms associated with perimenopause.

At this point, your ovaries are no longer releasing eggs or producing much estrogen. Physical changes during this time can increase your risk of:

Consult with a healthcare professional about lifestyle changes and other strategies you can implement to protect against these and other age-related health conditions.

Although most people have begun the transition into menopause or postmenopause by this time, a small percentage of people experience late menopause.

Late menopause refers to the onset of perimenopause after age 55. This isn’t necessarily a bad thing.

Older research has linked late menopause to a reduced risk of:

It’s also linked to a longer life expectancy. Researchers believe that prolonged exposure to estrogen protects the heart and bones.

Once a full year has passed since your last period, you’re officially in the postmenopausal phase. You may still have some of the same symptoms you experienced during perimenopause and menopause.

And if you’ve already been through menopause, it doesn’t always mean you’re done with all the symptoms.

A 2018 questionnaire-based study of 2,020 women ages 40–65 years found that 40% of adults still experienced hot flashes during this time.

The transition to menopause begins and ends at different times. Factors like your family history, personal health history, and whether you smoke can all impact the timing.

If you think you’re in perimenopause or menopause, consult with a healthcare professional. They can perform a blood test to make or confirm a diagnosis.

Tess Catlett is a sex and relationships editor at Healthline, covering all things sticky, scary, and sweet. Find her unpacking her inherited trauma and crying over Harry Styles on Twitter.