Is it perimenopause or something else?

Perimenopause has now entered the mainstream conversation. But with increased awareness comes a new challenge: the tendency to attribute every health change in your 30s and 40s to hormones. 

While hormonal fluctuations can cause a wide range of symptoms, treating perimenopause as a catch-all explanation could delay the diagnosis of other conditions—such as thyroid conditions or iron deficiency. 

To find out more, we spoke with Eve Lepage, MSN, RN, from Clue’s Science Team to break down how to spot the difference between typical cycle-led shifts and signals that might point to something else.

Key takeaways: 

• Common perimenopause symptoms—like brain fog, fatigue, mood shifts, and sleep issues—can overlap with conditions such as thyroid disorders and iron deficiency or anemia.

• You may be able to tell the difference by paying close attention to your cycle. Perimenopause symptoms often fluctuate and appear alongside changes to your cycle, while symptoms that persist independently of your cycle may warrant investigation for other causes.

• Even when symptoms are linked to perimenopause, you do not have to endure symptoms that are affecting your quality of life. Treatment options and support are available.

What are perimenopause symptoms?

Perimenopause symptoms stem from fluctuating hormone levels (particularly estrogen and progesterone). Because they fluctuate rather than decline steadily, symptoms can be wide-ranging and inconsistent. 

Common symptoms include:

• Changes to the menstrual cycle, such as longer or shorter cycles, heavier or lighter bleeding

• Hot flashes and night sweats

• Sleep disturbances

• Mood changes, including anxiety, irritability, or low mood

• Brain fog or difficulty concentrating

• Vaginal dryness and changes in libido

• Headaches or worsening migraines

• Joint aches or muscle pain

Not everyone will experience all of these, or with the same intensity. Symptoms may also change over time, making it difficult to understand what is happening.

When might it not be perimenopause?

One of the challenges with perimenopause is that many of its symptoms overlap with other health conditions. It’s easy to attribute changes to hormones, especially in your late 30s or 40s. 

But doing so can sometimes delay the correct diagnosis. 

Conditions and experiences that may cause overlapping symptoms include:

Thyroid disorders

Fatigue, mood changes, weight changes, and irregular periods can occur with both thyroid disorders and perimenopause. A blood test can help rule this out.

Iron deficiency or anemia

Heavy or prolonged bleeding during perimenopause can contribute to iron deficiency. Symptoms such as fatigue, brain fog, dizziness, shortness of breath, and heart palpitations may be misattributed to hormones when iron levels are actually the issue. 

Depression or anxiety disorders

Hormonal changes can affect mood, but persistent or severe symptoms may need dedicated mental health assessment and support.

Sleep disorders

Sleep disruption is common in perimenopause, but underlying sleep conditions (like sleep apnea) can also be at play, especially if sleep disruption is severe or longstanding. 

PMOS (formerly PCOS)

In some cases, irregular cycles and hormonal symptoms may reflect PMOS rather than perimenopause, particularly if these patterns have existed for years. 

Chronic stress and burnout

Prolonged stress can contribute to fatigue, brain fog, sleep disruption, and mood changes. It may mimic or intensify symptoms associated with perimenopause.

Pregnancy, medications, hormonal contraception, and conditions affecting the uterus or ovaries can also cause cycle changes or overlapping symptoms. A healthcare provider can consider your age, health history, symptoms, and cycle pattern and decide whether any tests are needed.

Can you tell the difference between perimenopause and another condition?

You may be able to tell the difference between perimenopause and another health condition by paying close attention to your cycle.

Changes to the menstrual cycle are often an early sign of perimenopause. Other symptoms may appear around the same time, fluctuate, or change over the course of the transition.

For example:

• Symptoms may cluster around certain points in your cycle

• Period timing may shift, but still follows a hormonal rhythm

• New symptoms appear alongside cycle changes

Tracking cannot confirm perimenopause or rule out another cause. However, recording when symptoms begin, how often they occur, how severe they are, and whether they occur alongside cycle changes can provide useful information for you and your healthcare provider.

How can tracking help with perimenopause?

One of the biggest challenges with perimenopause is that no single symptom can confirm it. Hot flushes, anxiety, poor sleep, and brain fog can all have several possible causes. This is where tracking can be particularly useful.

Looking at how your symptoms and cycle change over time can help build a clearer, more objective picture that can inform conversations with a healthcare provider.

Tracking can help you notice:

• Changes in your cycle pattern: Perimenopause often shows up first as subtle shifts in cycle length. Periods may be closer together, further apart, or become more variable month to month. 

• New symptoms appearing around the same time as cycle changes: For example, if sleep disruption, night sweats, or headaches begin at the same time as your cycle becomes irregular, this may point more strongly toward hormonal changes. 

• Escalation or clustering of symptoms: Rather than isolated symptoms, perimenopause often involves a cluster of physical, emotional, and cognitive changes that evolve together. 

• What’s not changing with your cycle: Symptoms that are persistent, worsening, or completely unrelated to any cycle pattern, for example, ongoing fatigue, low mood, or dizziness) may suggest something else is going on and should be investigated separately.  

And importantly, tracking can also help you distinguish between what might be considered typical perimenopause symptoms and those that are atypical or more concerning.

While changes like irregular periods, occasional hot flushes, or mild sleep disruption are common, symptoms that are severe, sudden, or significantly worsening, such as very heavy or prolonged bleeding, debilitating mood changes, or extreme fatigue, shouldn’t be dismissed as “just hormones.” 

These may still be related to perimenopause, but they warrant further investigation to rule out other causes and to ensure the right support is in place.

Crucially, even when symptoms are linked to perimenopause, that doesn’t mean they have to be tolerated. There’s a long-standing narrative that this is something to simply push through, but that’s changing. 

A range of treatment options are available, from menopausal hormone therapy (MHT, also known as HRT) to non-hormonal approaches, as well as support for specific symptoms such as sleep, mood, or heavy bleeding. If symptoms are interfering with your day-to-day wellbeing, that’s reason enough to seek care and explore what might help.

Perimenopause is a natural transition, but it shouldn't become a catch-all explanation for every new symptom. Nor should anyone have to suffer through symptoms that are affecting their quality of life. 

The bottom line is, if something feels off:

• Look for patterns over time

• Track symptoms alongside your cycle

• And seek medical advice to rule out other causes and find relief