Perimenopause

Why Are My Periods Changing in My 40s?

2026-06-25 · 2:01 · Perimenopause

The short answer

Why are your periods changing in your 40s? The most likely reason is perimenopause, the natural transition toward menopause. As your ovaries gradually wind down, your hormones start to fluctuate, and your periods change with them. Let me explain what's normal.

In this video

Most likely perimenopause, the transition toward menopause

You start ovulating less regularly, so periods get erratic

In your forties, you start ovulating less regularly. Some months you release an egg, some months you don't. Because your period depends on that hormonal rhythm, when ovulation gets erratic, so do your periods.

Closer, further apart, heavier, lighter, or skipped

These changes can take many forms: cycles that come closer together or further apart, periods that get heavier or lighter, shorter or longer, or months you skip entirely. It can feel unpredictable, and that unpredictability is itself the pattern of perimenopause.

Often starts mid-40s and lasts several years

This can start in your mid-forties, sometimes earlier, and continue for several years until your periods stop completely. Tracking your cycles in an app like PinkyBloom makes the shift visible, so you can see it's a trend, not a one-off.

If you're not pregnant, this is usually a normal transition

So if your once-regular periods are suddenly all over the place in your forties, and you're not pregnant, this is usually a normal, expected part of the transition, not a sign something's wrong.

But check: very heavy, bleeding between periods, or after 12 months none

That said, some changes do deserve a check: very heavy bleeding or large clots, bleeding between periods or after sex, periods closer than three weeks apart consistently, or any bleeding after you've gone a full year without one. Those are worth getting looked at.

PinkyBloom, link in description. Educational only, not medical advice.

So, to recap: periods changing in your forties is usually perimenopause, as irregular ovulation makes your cycles unpredictable, heavier or lighter, closer or further apart. It's normal, but very heavy bleeding, bleeding between periods, or bleeding after a year with none deserves a doctor. PinkyBloom helps you see the trend, link's in the description. This video is general education, not a substitute for professional medical advice. Take care, and I'll see you in the next one.

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Part of the Perimenopause guide →Read Perimenopause answers →Watch on YouTube →