When Does Perimenopause Start? Age, Risk Factors and Early Onset

Perimenopause usually starts in the mid-to-late 40s. Most people then reach menopause between 45 and 55. Some notice changes around 40, and a smaller number earlier. Genetics, smoking, ethnicity and medical treatment can all shift the timing. If you have menopause-type symptoms before 45, it is worth speaking to a doctor.

What is the average age perimenopause starts?

The US Office on Women’s Health says perimenopause usually begins in the mid-to-late 40s. The World Health Organization notes that natural menopause generally happens between 45 and 55 in women worldwide.

The final period itself comes later. In the United States, the average age of the last period is 51. A UK study of two national birth cohorts reports that, among White women in high-income countries, natural menopause happens on average between 50 and 52, and around 10% reach it before 45.

Averages differ between countries and populations, and your own timing may sit well outside them.

For what perimenopause is and how it progresses, see our complete guide to perimenopause.

What affects when perimenopause starts?

Menopause timing reflects how many egg-containing follicles you were born with and how quickly they are used up. Several factors are linked with an earlier or later start. These are associations across large groups, not guarantees for any one person.

Genetics and family history

Genetics play a major role. Researchers estimate that genes account for about half of the variation in when menopause begins. In the Study of Women’s Health Across the Nation (SWAN), having a mother who reached natural menopause before 49 was linked with an earlier final period.

Your mother’s or older sisters’ experience is a reasonable starting clue, but it cannot tell you your own age.

Smoking

Smoking is the lifestyle factor most consistently linked with earlier menopause. One review estimates it brings menopause forward by about 1.5 to 2 years, and a meta-analysis of 15 studies found close to one year earlier. Heavier smoking appears to have a larger effect in some studies.

There is encouraging news: a large international meta-analysis found that former smokers reached menopause at a similar age to people who had never smoked.

Ethnicity

US research suggests Black and Hispanic women may reach menopause roughly two years earlier than White or Asian women, according to Women’s Health Concern, the British Menopause Society’s patient charity. SWAN also found that women who were not White or Japanese tended to have an earlier final period.

These differences probably reflect a mix of genetic, social and health factors rather than ethnicity alone.

Reproductive history and health

• Never having given birth and shorter menstrual cycles have been linked with earlier menopause.
• Removal of one ovary is associated with an earlier menopause, by about a year in one study.
• Having had diabetes was associated with an earlier final period in SWAN.

Social circumstances

In SWAN, women who found it difficult to pay for basics tended to reach their final period earlier. Studies differ on how strong this link is, but it suggests life stress and access to healthcare may matter too.

Medical treatment

Surgery to remove both ovaries brings on menopause immediately, whatever your age. Chemotherapy and pelvic radiotherapy can also cause an earlier or sudden menopause. If you have had any of these treatments, ask your care team what to expect.

Can you predict when perimenopause will start?

Not with any precision. This is one of the most common questions, and the honest answer is that no test gives a reliable date.

• Anti-Müllerian hormone (AMH). A 2023 systematic review found that lower AMH is linked with earlier menopause, but AMH alone could not predict the age at menopause precisely. For women under 40, estimates ranged across 2 to 12 years.
• Combined approaches. Researchers have tried combining bleeding patterns, FSH and AMH. Even then, they could only predict the final period within a window of about four years.
• Home tests measure FSH, which rises and falls from month to month during this stage. They cannot tell you when perimenopause will begin or end.

Your family history and your own cycle pattern are, in practice, as useful as any test. For more detail, see our guide to what perimenopause tests can and can’t tell you.

Can you delay perimenopause?

There is no proven way to delay natural menopause. The one factor with good evidence is smoking, and stopping appears to remove much of its effect on timing.

Hormonal contraception does not delay menopause either. According to the UK Faculty of Sexual and Reproductive Healthcare (FSRH), contraception does not change when menopause happens. It can, however, make it harder to notice, because some methods cause regular bleeds while others stop periods altogether.

Does starting earlier mean a longer perimenopause?

Often, yes. Research summarized by the US Centers for Disease Control and Prevention found that women who enter the menopause transition earlier tend to have longer transitions. SWAN also found that women whose hot flashes began earlier in the transition tended to have them for longer.

See how long perimenopause lasts for the full timeline.

What if perimenopause starts early?

Two terms are used when menopause happens earlier than usual:

• Early menopause: menopause between 40 and 44
• Premature ovarian insufficiency (POI): menopause before 40, sometimes called premature menopause

Earlier menopause matters for long-term health, not just symptoms. Large population studies link early natural menopause with higher risks of heart disease, osteoporosis, type 2 diabetes and earlier cognitive decline.

That is why guidance treats early menopause differently. The Menopause Society recommends that people with POI or early menopause can use hormone therapy until at least the average age of natural menopause, unless there is a reason not to. NICE advises offering psychological support to people aged 40 to 44 who are distressed by an early menopause diagnosis.

See a doctor if you are under 45 and have menopause-type symptoms, or if your periods stop before 40. Our guide to early menopause explains diagnosis and treatment, and menopause at 40, 45, 50 and beyond covers what your age means. Under 45, blood tests play a bigger role in diagnosis. You can read more in our guide to perimenopause tests.

How do you know if it has started?

For most people, the first sign is a change in periods: cycles that become shorter or longer by a week or more, heavier or lighter bleeding, or skipped periods. Others first notice sleep changes, mood shifts or hot flashes while their cycle still looks normal.

Our guide to the early signs of perimenopause explains what to look for. Keeping a record of your periods and symptoms for two or three months makes patterns much easier to spot. Our private Symptom Explorer can help you do that.

When should you see a doctor?

Book an appointment if:

• You are under 45 and think you have menopause symptoms
• Your periods have stopped for several months and you are under 40
• Symptoms are affecting your sleep, work or relationships
• You want to discuss contraception or treatment

Get checked promptly if you have:

• Bleeding after sex or between periods
• Very heavy bleeding, such as soaking through a pad or tampon every hour for several hours
• Any bleeding 12 months or more after your last period

Our guide to preparing for a perimenopause appointment covers what to bring and what to ask.

Questions to ask your doctor

1. Given my age and symptoms, is this likely to be perimenopause?
2. Does my family history change what you would expect?
3. Do I need any tests, or can this be identified from my symptoms?
4. If this is an early menopause, what does that mean for my bones and heart?
5. Do I still need contraception? Our guide to pregnancy during perimenopause explains why you might.

Frequently asked questions

Can perimenopause start at 35?

It is uncommon but possible. Changes in your late 30s are more often caused by something else, so it is worth seeing a doctor to check. Menopause before 40 is called premature ovarian insufficiency and needs medical assessment.

Is 40 too early for perimenopause?

No. Some people start noticing changes around 40, although the mid-to-late 40s is more typical. If your periods stop completely between 40 and 44, that is classed as early menopause, and it is worth discussing with a doctor.

Will I go through menopause at the same age as my mother?

Possibly around the same time, because genetics play a large part. It is only a rough guide, though, and smoking, health conditions and treatments can shift your timing.

Does taking the pill delay menopause?

No. Hormonal contraception does not change when menopause happens, but it can make it harder to tell when perimenopause has started.

Does perimenopause start earlier in some countries?

Average ages vary between populations. The WHO’s global range for natural menopause is 45 to 55. Differences are thought to reflect genetics, health, nutrition and social factors.

References

1. World Health Organization: Menopause fact sheet
2. US Office on Women’s Health: Menopause basics
3. ACOG: Perimenopausal bleeding and bleeding after menopause
4. Gold EB et al. Factors related to age at natural menopause: longitudinal analyses from SWAN
5. Schoenaker DAJM et al. Socioeconomic position, lifestyle factors and age at natural menopause: a systematic review and meta-analyses. International Journal of Epidemiology, 2014
6. Determinants of the age at natural menopause (review), PubMed
7. Factors affecting age of onset of menopause (review), PMC
8. Risk factors for natural menopause before the age of 45: two British birth cohorts
9. Prenatal maternal smoking and time to natural menopause: two UK birth cohorts
10. Women’s Health Concern (British Menopause Society): Perimenopause and menopause fact sheet, April 2026
11. Anti-Müllerian hormone for the diagnosis and prediction of menopause: a systematic review. Human Reproduction Update, 2023
12. Healio: Is an at-home menopause test useful for women?
13. CDC Stacks: Menstrual cycle changes as women approach the final menses
14. FSRH Contraception Choices: Perimenopause and menopause
15. NICE guideline NG23: Menopause, identification and management
16. The 2022 hormone therapy position statement of The North American Menopause Society

Editorial status: evidence-based educational article. Last evidence check: September 10, 2026.