Are your periods suddenly heavier, coming closer together, or becoming completely unpredictable? Understandably, you might be wondering whether this is a normal part of perimenopause.

Changes in your menstrual cycle are often one of the earliest signs of perimenopause. But while they’re common, that doesn’t mean every change should automatically be dismissed as normal.

Understanding why your periods are changing, what to watch for, and when to seek medical advice can help you make more informed decisions about your health.

Why do periods change during perimenopause?

One of the biggest changes during perimenopause is that ovulation becomes less predictable.

During our reproductive years, ovulation typically happens fairly consistently. As we approach menopause though, some cycles may involve normal ovulation, others may involve delayed ovulation, and sometimes ovulation doesn’t happen at all.

This matters because progesterone is produced primarily after ovulation. When ovulation becomes less consistent, so does progesterone production. Meanwhile, estrogen levels can fluctuate considerably, sometimes reaching higher levels than earlier in our reproductive years.

These fluctuations affect how the uterine lining builds up and sheds, which is one reason menstrual bleeding can become less predictable.

Some of the common changes include:

  • Periods that come closer together or farther apart

  • Skipped periods

  • Heavier or lighter bleeding

  • Periods that last longer than usual

  • Changes in PMS symptoms, breast tenderness, or menstrual cramps

Every woman’s experience is different, and these patterns may continue to change throughout perimenopause.

What Are the Causes of Heavy or Irregular Bleeding

While hormonal fluctuations can explain many of these changes, it’s important not to assume that perimenopause is always the cause.

Other possibilities include:

  • Fibroids: Noncancerous growths in the uterus that can contribute to heavy or prolonged menstrual bleeding.

  • Uterine polyps: Growths in the uterine lining that may cause irregular bleeding or spotting between periods.

  • Adenomyosis: A condition where tissue similar to the uterine lining grows into the muscular wall of the uterus, sometimes causing heavy, painful periods.

  • Thyroid dysfunction: Both underactive and overactive thyroid conditions can affect menstrual patterns.

Changes in the uterine lining, including endometrial hyperplasia and, less commonly, cancer, are other important reasons that certain bleeding patterns need further investigation.

Heavy periods can also contribute to iron deficiency and anemia, which may leave you feeling exhausted, short of breath with activity, or struggling with concentration. These symptoms can easily be mistaken for other changes associated with midlife.

When Should You See A Doctor About Period Changes?

Some variation in your menstrual cycle is expected during perimenopause, but there are changes that warrant medical attention.

Make an appointment with your healthcare provider if you’re experiencing:

  • Periods that are unusually heavy or interfere with your daily activities or quality of life

  • Bleeding that regularly lasts longer than seven days

  • Periods that repeatedly occur less than 21 days apart

  • Bleeding between periods or after sex

  • New or worsening pelvic pain

  • Any bleeding after 12 consecutive months without a period

If you’re soaking through a pad or tampon every hour for several hours, seek urgent medical assessment. Heavy bleeding accompanied by fainting, severe dizziness, chest pain, or shortness of breath may require emergency care.

What Can You Do?

The first step is getting a clear picture of what’s happening rather than assuming it’s simply perimenopause.

Tracking your cycle can be helpful. Make note of when your period starts, how long it lasts, how heavy the bleeding is, and whether you’re noticing spotting, pain, or other symptoms.

From there, a thorough assessment with your healthcare provider can help determine what further investigation makes sense. Depending on your age, medical history, symptoms, and risk factors, this might include blood work to assess for anemia or iron deficiency, thyroid testing when indicated, pelvic ultrasound, or an assessment of the uterine lining.

A single estrogen or progesterone blood test usually isn’t particularly helpful for evaluating irregular bleeding during perimenopause because hormone levels often fluctuate considerably during perimenopause.

Once there’s a better understanding of what’s happening, treatment options can be discussed. Depending on the cause, these may include herbs, nutrients (like iron), medications, hormonal treatments, or procedures.

There are options, and the right approach depends on your individual circumstances.

The Bottom Line

Changes in your periods are a common part of perimenopause, but not every change should automatically be attributed to hormones. Just because something is common doesn’t mean you have to accept the impact it’s having on your quality of life.

If you’re navigating perimenopause and would like help understanding your symptoms, identifying appropriate investigations, and developing a plan that supports your health, I’d love to help.

Learn more about how I can help

References:

Marnach, M. L., & Laughlin-Tommaso, S. K. (2019). Evaluation and Management of Abnormal Uterine Bleeding. Mayo Clinic Proceedings, 94(2), 326–335. https://doi.org/10.1016/j.mayocp.2018.12.012

Medeiros, S. F. D., Yamamoto, M. M. W., & Barbosa, J. S. (2013). Abnormal Bleeding during Menopause Hormone Therapy: Insights for Clinical Management. Clinical Medicine Insights: Women's Health, 6, CMWH.S10483. https://doi.org/10.4137/cmwh.s10483

Merck Manual. (2023). Abnormal uterine bleeding. https://www.merckmanuals.com/en-ca/professional/gynecology-and-obstetrics/menstrual-abnormalities/abnormal-uterine-bleeding [2] [3]

This article is for educational purposes and isn’t a substitute for personalized medical advice. Speak with your healthcare provider about changes in your menstrual bleeding or symptoms that concern you.