Perimenopause and irregular periods: what's common, what's not

Irregular periods — closer together, farther apart, heavier, lighter, or skipped — are one of the earliest and most common signs of perimenopause [1]. NICE guidance uses a change in your menstrual cycle, alongside other symptoms, as one of the signs clinicians look for when identifying perimenopause in people 45 and over [1]. Most cycle changes in this transition are ordinary. Some bleeding patterns are not, and are worth a prompt call to a clinician.

This page was written by the Softa editorial team using NICE, NHS, ACOG, and Cleveland Clinic guidance; it has not yet been clinically reviewed.

Are irregular periods normal in perimenopause?

Yes, for most people. Cleveland Clinic states plainly that "irregular periods are common and normal during perimenopause," while also noting that other conditions can cause irregular bleeding too [2]. As estrogen and progesterone levels swing rather than decline steadily, your cycle length, flow, and predictability often change along with them.

What "irregular" can actually look like

"Irregular" isn't only "you skipped a month." It can show up as:

• Cycles becoming shorter (periods closer together)
• Cycles becoming longer or unpredictable
• Flow much heavier or lighter than your own baseline
• Spotting between periods
• Periods lasting longer than usual for you

What counts as a change is relative to your history, not a textbook 28-day cycle. A shift from your own normal is usually more informative than comparing yourself to an average.

When does irregularity cross into "abnormal uterine bleeding"?

Clinically, there's a line between expected cycle changes and bleeding that needs evaluation. ACOG defines abnormal uterine bleeding as including: bleeding or spotting between periods, bleeding or spotting after sex, bleeding that soaks through one or more pads or tampons every hour, bleeding lasting more than 7 days, cycles longer than 35 days or shorter than 21 days, cycle length varying by more than 7–9 days, not having a period for 3–6 months, or any bleeding after menopause [3].

Pattern	Usually a perimenopause change	Worth flagging to a clinician
Cycle length	Shifts of a few days from your usual	Cycles consistently under 21 or over 35 days [3]
Flow	Somewhat heavier or lighter than your baseline	Soaking a pad or tampon every hour for several hours; periods lasting more than 7 days [3]
Timing	Occasional skipped or early period	Spotting or bleeding between periods, or after sex [3]
After no period for months	—	Any bleeding at all once you've gone 12 months without a period [1]

Why the 30s and 40s confuse people

Many people were taught that menopause is a story about your 50s. Perimenopause can begin well before that — ACOG describes estrogen fluctuation as "beginning in your 30s and 40s" for some people [4]. That doesn't mean every irregular cycle in your 30s or 40s is perimenopause. Stress, thyroid changes, PCOS, medication, and pregnancy or postpartum transitions can all affect your cycle too. The useful move isn't self-diagnosing — it's tracking what's changing and bringing that to a clinical conversation when something worries you.

What to log (for you and your clinician)

• Date bleeding started and stopped
• How heavy it felt — pad/tampon changes per hour, or clots larger than about a coin
• Pain level and location
• Sleep, stress, travel, or illness around that cycle
• Any new medications or supplements

A couple of unusual months can feel like a fluke. A logged stretch becomes a pattern a clinician can actually use.

When to see a clinician

See a clinician promptly if…
You soak a pad or tampon every hour for several hours, or your period lasts far longer than usual for you [3]
You bleed or spot between periods, or after sex [3]
Your cycles are consistently shorter than 21 days or longer than 35 days [3]
You bleed at all after 12 months with no period [1]
Heavy bleeding comes with chest pain, shortness of breath, or feeling lightheaded — seek emergency care [3]
Irregular periods come with new heavy fatigue — worth checking for anaemia alongside the bleeding pattern

How Softa helps with irregular periods

Classic period-tracking apps often assume a tidy, predictable cycle and try to predict your next one from it. That approach breaks down in perimenopause, when the whole point is that cycles stop being predictable. Softa logs bleeding and symptoms together instead of forcing a prediction, so you can see how your cycle is actually behaving over weeks and months — and bring a clear summary to a clinician instead of a foggy memory of "it's been weird lately." Softa does not diagnose the cause of irregular bleeding.

Start the check If irregular periods are one part of a bigger pattern, Softa's short assessment can help you organize what else to watch. Start the check →

For the broader symptom picture, see perimenopause symptoms. If you're wondering whether a blood test can confirm what's going on, see perimenopause test — cycle changes alone don't require one. And for treatment options if bleeding itself needs managing, see perimenopause treatment.

Sources

1. NICE. Menopause: identification and management (NG23), Recommendation 1.3.1. 2015, updated 2024/2026. nice.org.uk/guidance/ng23/chapter/recommendations
2. Cleveland Clinic. Perimenopause: Age, Stages, Signs, Symptoms & Treatment. Accessed 2026. my.clevelandclinic.org/health/diseases/21608-perimenopause
3. ACOG. Abnormal Uterine Bleeding. Accessed 2026. acog.org/womens-health/faqs/abnormal-uterine-bleeding
4. ACOG. The Menopause Years. Accessed 2026. acog.org/womens-health/faqs/the-menopause-years
5. NHS. Heavy periods. Accessed 2026. nhs.uk/conditions/heavy-periods