When Does Perimenopause Start — and How Long Does It Last?

You’ve heard the word perimenopause tossed around. But how do you know if you’ve actually started it?
And how long does this confusing, unpredictable stage even last?

The truth is, perimenopause often starts earlier than most women expect—and it doesn’t follow a fixed schedule.

In this article, we’ll break down:

• When perimenopause usually begins
  
• How long it can last
  
• The most common signs that it’s started
  

You’ll walk away with clarity—and the tools to feel more in control.

What Is Perimenopause?

Perimenopause is the transition phase before menopause—when your body begins to shift away from its reproductive years.

During this time, your ovaries gradually produce less estrogen and progesterone, triggering a wide range of physical, mental, and emotional symptoms.

The transition isn’t sudden. Think of it like the dimming of a light—gradual, inconsistent, and different for every woman.

Once you’ve gone 12 consecutive months without a period, you’ve officially entered menopause. Everything before that? That’s perimenopause.

According to the North American Menopause Society, perimenopause typically begins between ages 40 and 44, but can start as early as your mid-30s.

When Does Perimenopause Typically Start?

Most women begin perimenopause in their early to mid-40s, but it’s not uncommon to experience early signs in your late 30s.

Signs It May Be Starting:

• Your period arrives a few days early… or late
• Your mood feels off even though nothing has changed
• You’re suddenly more sensitive to stress or less tolerant of noise, chaos, or caffeine.
• You’re waking up at 3 AM for no reason
• Your PMS feels more intense, or your breast tenderness worsen.s

These are your body’s early signals that hormone levels are fluctuating—especially estrogen.

How Long Does Perimenopause Last?

There’s no one-size-fits-all timeline—but here’s what research and clinical data show:

A 2021 study from the Journal of Women’s Health found that some women experience vasomotor symptoms (like hot flashes) for up to 11 years—well before and after menopause itself.

It’s also worth noting that the length of perimenopause doesn’t predict how severe your symptoms will be. Some women breeze through a long transition, while others struggle through a short one.

Timeline Breakdown: What to Expect

What Factors Influence When It Starts?

Every woman’s body is different, but several factors can affect the onset and duration of perimenopause:

• Genetics: Your mother’s menopause timing is a strong predictor
• Smoking: Linked to earlier menopause by up to 2 years
• Autoimmune issues or PCOS: May delay or accelerate hormone changes
• Surgical interventions: Hysterectomy or ovarian removal causes immediate menopause
• Chemotherapy/radiation: Can induce early menopause or disrupt normal transition

Expert Tip

💡 “While blood tests can give some insight, the most accurate way to identify perimenopause is by tracking your symptoms over time. Hormone levels fluctuate too much for a one-time result to tell the full story.”
— Dr. Mary Jane Minkin, OB-GYN and menopause expert, Yale School of Medicine

Common Early Symptoms That Signal It’s Starting

These often appear 2–4 years before major cycle disruptions:

• Mood changes (new anxiety, emotional reactivity)
• Sleep issues (trouble falling or staying asleep)
• Heavier or lighter periods
• Increased PMS symptoms
• Hot flashes or night sweats
• Low libido
• Brain fog or forgetfulness

Even if your period still arrives like clockwork, your hormones may already be shifting. That’s why many women miss the early signs.

Why You Might Not Realize It’s Perimenopause

• You’re still having your period, so it “can’t be menopause,” right?
• Your doctor said your blood work looks normal.
• You chalk it up to stress, ageing, or parenting fatigue.
• No one warned you this could happen in your 30s

Unfortunately, many women are gaslit by the medical system or misdiagnosed with depression, anxiety, or thyroid issues when the root cause is hormonal.

What You Can Do to Take Control

Recognizing you’re in perimenopause is powerful. Here’s what you can do:

• Track your symptoms: Use a journal or app to monitor mood, sleep, cycle, and energy
• Take a quiz: Use a science-backed tool to identify what stage you’re in
• Support your body: Sleep, movement, stress management, and nutrition all help
• Talk to a doctor: Look for one familiar with women’s hormonal transitions

💡 Myth vs Reality

What You Can Do Next

Don’t wait until your symptoms feel overwhelming. Start learning what’s going on in your body now so you can:

• Take preventive steps
• Minimize discomfort
• Feel confident through the changes ahead.

Awareness is your greatest asset whether you’ve just started noticing shifts—or you’re deep in the fog.

Sources

• North American Menopause Society

• PubMed: J Womens Health. 2021

• Mayo Clinic – Perimenopause

• NIH – Hot Flashes and Menopause Duration

Anna Haotanto

Anna Haotanto is the Founder of Zora Health and a passionate advocate for women’s empowerment. Anna’s personal experiences with egg-freezing, PCOS, perimenopause and the challenges of fertility have fueled her mission to provide high-quality information, financing, and support to help women and couples navigate their fertility journeys with confidence. She is also recognised for her achievements in finance, entrepreneurship, and women’s empowerment, and has been featured in various media outlets. You can also follow her on Linkedin or Instagram.