Period changes in perimenopause are often surprises

Period Changes in Perimenopause: What You Need to Know

Period changes in perimenopause are very common. Very common and often very surprising. As with most symptoms during this lead up to menopause, most of us aren’t aware of what can happen in perimenopause until it does.

During this transitional phase levels of estrogen and progesterone, the hormones that regulate your menstrual cycle, can vary greatly, leading to changes in your period’s regularity. You might find that your periods come more closely together, or alternatively, they could be farther apart. It’s not uncommon to skip periods during perimenopause, or to experience heavier or lighter bleeding than what was typical for you earlier in life.

Timing of Perimenopause

Typically, perimenopause begins sometime in your 40s, but it can start as early as your late 30s. It’s important to remember that your age doesn’t dictate the exact onset of perimenopause; it’s more about how hormone levels change as you approach menopause. (More on why that’s important below.) As estrogen and progesterone levels fluctuate and eventually decrease, your fertility reduces. This period of transition can vary in length, lasting anywhere from a few, to ten or more years before reaching menopause, which is when your periods stop altogether.

Yes, you read that last sentence correctly. Perimenopause can last 10 or more years for some people.

Does Perimenopause = Period Changes?

Some doctors will tell you that if you aren’t experiencing changes to your menstrual cycle then you aren’t in perimenopause. Indeed, I spent several years in my early 40s trying to figure out why I kept waking up at 2 am (for the day), having terrible mood swings, and horrible PMS symptoms. The practitioners I consulted at the time didn’t even consider perimenopause. And if they did, that potential cause was quickly dismissed because my periods hadn’t changed.

Turns out that you don’t need to experience noticeable period changes to be in perimenopause. You also don’t need to be as old as most people (and some doctors) think.

New Research by Women Living Better

In a study conducted by Women Living Better and published in Menopause: The Journal of The North American Menopause Society (now known as The Menopause Society), it was established that long before menstrual irregularities occur, perimenopausal symptoms including things like night waking, unprecedented anxiety, increased premenstrual headaches, and weight gain can occur.

They identified two phases leading up to menopause, which is officially diagnosed one year after your final menstrual period. In the first phase, ‘estrogen levels are erratic with higher-than-normal, chaotic spikes throughout the cycle’. Progesterone may be declining in this phase. And monthly periods are still happening, but with subtle changes in length, number of days, and/or amount of flow. Looking back, I’m sure there were slight differences in my period, but nothing significant enough to respond “yes”, to the question about whether my periods had changed.

The second phase is characterized by irregular cycles and ‘estrogen levels that begin to decline but may be erratic and high at times’. Progesterone continues to decline in this phase. It is typically in this phase where symptoms like hot flashes and vaginal dryness show up. You can find a summary of this research here.

The team at Women Living Better notes that these phases don’t necessarily happen in a linear fashion. For example, you may skip a period and then start getting regular periods again for some time. Each person’s experience is unique. And as noted above, often full of surprises.

What Are Period Changes in Perimenopause?

We’ve read that the term perimenopause was first introduced in 1996. And I guess this isn’t surprising since women weren’t permitted to participate in clinical trials until 1991. We still don’t know what we should about perimenopause, or women’s health in general, but let’s stick to perimenopause for now. Most of us are blindsided when symptoms present due to hormonal changes as our reproductive capabilities start to change. Especially when we don’t have a healthcare provided who has undertaken to better understand menopause and its related stages. Menopause and it’s related stages still get little to no attention in medical school curriculums. Sigh.

Here is an overview about what period changes in perimenopause can mean and when you should get help.

Irregular Periods and Spotting

Your periods may become more irregular during perimenopause, with bleeding becoming unpredictable. You might experience spotting between periods or have missed periods, which is often a normal part of the transition. It is recommended to have spotting checked out by your doctor to rule our other causes.

Cycle Length Variations

The length of your menstrual cycles may vary more than before. Some cycles may be noticeably shorter, while others could be longer. It’s also not unusual for the length of time between periods to change from month to month. Really short cycles should be reviewed by your doctor, particularly to ensure your iron levels aren’t suffering.

Changes in Flow and Menstrual Symptoms

You may notice changes in your menstrual flow with heavier bleeding or lighter periods than usual. The appearance of clots can also occur. In addition to flow changes, symptoms such as cramps may either intensify or diminish during this phase. Clots larger than a grape and bleeding that meets any of the criteria listed in the bullets below should be checked out by your medical provider.

Changes in Color

Due to changes in your hormonal patterns you may notice a change in color from bright red to brown. When estrogen plunges during your menstrual cycle, that’s when the lining of your uterus is shed and you start bleeding. When estrogen is fluctuating outside of your predictable hormonal pattern in perimenopause the uterine lining may break down at different times without being expelled. Because it isn’t shed right away the blood turns brown. According to Evernow, ‘basically, brown blood equals “old” blood’.

Changes in Premenstrual Symptoms

Hormonal fluctuations in perimenopause can make your premenstrual syndrome (PMS) or premenstrual dysphoric disorder (PMDD) worse. Women who’ve never experienced PMS before can develop these symptoms during perimenopause. These symptoms can include mood swings, anxiety, irritability, trouble sleeping, fatigue, headaches, bloating and other digestive issues, breast tenderness, acne, and changes in appetite and sex drive.

PMDD is a severe form of PMS. Although PMS and PMDD both have physical and emotional symptoms, PMDD causes extreme mood shifts that can disrupt daily life and damage relationships. The physical symptoms can also be quite severe. A PMDD diagnosis requires certain criteria. You can read more about PMDD here.

Symptoms with No Period

Wildly fluctuating hormones in perimenopause can also mean that even though you don’t get your period you can still have cramping and other premenstrual symptoms. And these symptoms can be really intense. Not to mention confusing and sometimes scary.  I’m speaking from experience.

When to Get Help

While period changes in perimenopause are common, there are signs you should address with your doctor. One of the most important being your discomfort. If you period changes in perimenopause are impacting your life, get help. Here are some of other scenarios that should be seen by a doctor:

  • Restriction of daily activities due to heavy menstrual flow.
  • Symptoms of anemia such as tiredness, fatigue, or shortness of breath.
  • Changing your soaking pad or tampon every one to two hours for a few hours (2-3).
  • Needing to wake up at night to change soaked sanitary protection.
  • Emptying your menstrual cup more often than recommended.
  • Needing multiple sanitary products at one time.
  • Flooding through your sanitary protection and clothes.
  • Passing clots that are larger than a grape.
  • Periods that last more than seven days.
  • Periods that are less than 21 days from the start of one period to the start of the next.
  • Spotting in between periods.
  • Bleeding after sex.
  • Any bleeding once you’ve achieved menopause requires a doctor’s visit.
  • Symptoms like severe pain and/or mood changes.

Health Considerations in Perimenopause

During perimenopause, your body goes through hormonal fluctuations that can affect both your fertility and menstrual health. Understanding these changes is essential for managing your overall well-being during this transition.

Fertility and Pregnancy Concerns

As you enter perimenopause, your fertility naturally decreases due to a decline in the number and quality of your eggs. Ovulation becomes less predictable, and progesterone levels decline when ovulation doesn’t occur. However, pregnancy is still possible. So if you wish to avoid pregnancy, continue using contraception until you have not had a period for at least 12 months. Should you experience a skipped period, it’s reasonable to take a pregnancy test to rule out pregnancy.

If you’re considering pregnancy during perimenopause, it’s important to discuss this with your healthcare provider to understand the difference in risks and what steps to take to support a healthy pregnancy.

Menstrual Health Conditions

Perimenopause can also lead to changes in the menstrual cycle that might confuse normal variations with conditions that require attention. Heavy bleeding could signal the development of uterine fibroids or polyps, which are noncancerous growths on the uterine lining. Additionally, conditions like adenomyosis, where the inner lining of the uterus breaks through the muscle wall, can cause pain and heavier periods. Heavy bleeding can also cause certain health conditions like Anemia. Conditions to be aware of include:

    • Uterine Fibroids: Can cause heavier bleeding and discomfort.
    • Endometrial Polyps: Abnormal growths in the uterine lining that may cause bleeding irregularities.
    • Blood Clots: An increase during periods could be a sign of underlying issues.
    • Endometrial Cancer: Though rare, heightened awareness is crucial for early detection.
    • Thyroid Disease: Too much or too little thyroid hormone can make your periods irregular and potentially cause amenorrhea, where your periods stop for several months or longer.
    • Iron Deficiency and Anemia: Heavy, lengthy, and/or frequent periods can make you iron deficient or even anemic.

If you notice any drastic changes in your menstrual cycle, it’s essential to seek advice from your healthcare provider to rule out serious conditions and to discuss possible treatments that can alleviate symptoms and manage the effects on your daily life.


The intent of this information is to provide the reader with knowledge to support more efficient and effective communication with their medical providers. This information is not intended as medical advice.