The Difference Between Perimenopause and PMS Symptoms

Many women struggle with symptoms of PMS on a monthly basis, but did you know that several of these symptoms can actually overlap with those experienced in perimenopause? In this article, we’ll take a look at common PMS and perimenopause symptoms along with the ways you can potentially tell the difference.

How Are PMS and Perimenopause Symptoms Different?

Women who have experienced premenstrual syndrome (PMS), and its symptoms  throughout their teens, 20s and 30s may be surprised to discover that during their 40s, the uncomfortable symptoms they’ve been coping with for years, are suddenly no longer due to PMS, but are actually signs of perimenopause. That’s because many of the symptoms of perimenopause – breast tenderness, irritability, mood swings, bloating, brain fog and decreased libido — can echo those of PMS.

PMS vs. Perimenopause, What’s the Difference?

Though their symptoms are somewhat similar, PMS and perimenopause are different. If your menstrual cycles occur consistently on a monthly basis, you can usually predict when you will get your period based on past cycles – give or take a few days. PMS is typically marked by the onset of symptoms at relatively the same time every cycle – typically mid-cycle with ovulation – and most importantly, there is a full resolution of these symptoms following menstruation. Perimenopause, on the other hand, is linked to more significant hormonal fluctuations and does not follow a typical 28-day cycle. As a result, symptoms of perimenopause may appear to be much more erratic.

Another difference is when the symptoms of PMS and perimenopause begin. Most young women get their first period around the age of 12, but this range can extend from as young as eight to up to 15 years old.¹ It’s at this time that PMS symptoms can begin. It’s been found that up to 90% percent of women experience at least one PMS symptom per month.²

In the case of teenagers, many may experience mood swings, irritability and anxiety, which are often attributed to changing hormones and their stage of emotional and physical development. However, mood swings and feeling down may also stem from PMS. Many women in their 20s, 30s and early 40s may also feel like they’re on an emotional rollercoaster right before their periods begin.³

While PMS starts at a young age, perimenopause and its symptoms begin later in life. According to the Mayo Clinic, perimenopause, which means “around menopause,” refers to the stage in a woman’s life when she naturally transitions to menopause, marking the end of her reproductive years.⁴ It can begin for some women in their 30s, but more often, perimenopause starts between the ages of 40-44 – and typically lasts 4-8+ years.^5,6

Hear more from Chief Medical Officer, Dr. Alyssa Dweck, on the differences between PMS and perimenopause in the brief video, below:

PMS and Perimenopause Symptoms – Some Similarities

Since PMS and perimenopause symptoms are somewhat similar, how can you tell which one you’re actually experiencing? Let’s do a quick comparison:

• Emotional symptoms. Irritability, anger and mood swings are not uncommon PMS and perimenopause symptoms. With PMS, these emotional ups and downs usually begin a week or two before your period begins and then subside a day or two afterwards.⁷ In contrast, mood swings can happen at any time during perimenopause. In fact, nearly 40% of women may experience sporadic mood swings during perimenopause, which can include anger, depression and anxiety.⁸

• Irregular menstrual cycles. Although women typically get their period approximately every 28 days, everyone’s body is different. Up to 25% of women may experience irregular periods during their reproductive years– meaning their periods are longer or shorter than the typical 28-day cycle or missed occasionally.⁹ Sometimes this is due to a hormonal imbalance or volatile hormonal fluctuations, like perimenopause. It could be due to other factors, such as extreme dieting or exercise, stress, pregnancy or illness.¹⁰ Most women continue to get their periods during perimenopause, but their cycles may become inconsistent. In some cases, your period, which may have averaged between five to seven days previously, may now only lasts two to three days. You may get your period again in two to three weeks, instead of following your usual 28-day cycle. You may even miss your period for a month or two, only to have it return again on a more regular basis.¹¹ The bottom line is that your period can become very unpredictable, and that goes for timing, as well as the heaviness of your flow during perimenopause.

Monitor Your Cycles to Help Tell the Difference Between PMS and Perimenopause

For those women who already have irregular cycles, keeping track of them can be an important part in telling the difference between PMS and perimenopause. There’s no perfect science in telling the difference, but it’s possible for your body to change “how” it is irregular. Keeping a log can help you track your cycle.

There are other symptoms you can be mindful of as well, including:

• Heavy bleeding. Some women bleed more than others during their period. During perimenopause, some women may experience a dramatic increase in menstrual blood. Aside from being inconvenient, heavy bleeding can lead to anemia.¹² Women with anemia may suffer from light-headedness, shortness of breath, chest pains, fast or irregular heartbeats, headaches, and a pale complexion.¹³ It’s important to see your healthcare provider if you experience abnormally heavy bleeding that’s vastly different from your “norm”.

• Hot flashes and night sweats. Although it’s possible to have hot flashes or night sweats as a PMS symptom, they are most often associated with women experiencing perimenopause (as well as those who are fully menopausal). The first few times you experience a hot flash you may simply think that the thermostat in the room is suddenly too high or that you’re coming down with a fever. Suddenly, you go from feeling fine to feeling like you’re on fire. Beads of sweat may appear, and your face may become flushed. When it passes, you may feel a cold chill. It’s not clear why hot flashes occur during perimenopause, but it’s often tied to hormonal fluctuations. The good news is that for most women, hot flashes usually become less frequent with time – but their frequency and duration can vary.¹⁴

• Brain fog. Ever feel a little forgetful or that you’re not thinking super clearly? It’s likely brain fog - this symptom can occur before your period,¹⁵ a time during which your hormones are fluctuating, or during perimenopause. There isn’t much difference between how women with PMS and those with perimenopause experience brain fog – meaning the symptom appears to present similarly in both groups. It’s also understandably equally frustrating for both. 

Although many of these symptoms are a normal part of life, it doesn’t mean you need to tough them out. There are a variety of prescription and over the counter solutions that can help both the physical and emotional symptoms experienced with PMS or during perimenopause. Be sure to talk to your healthcare provider to determine the best option for you.

Resources

1. https://www.womenshealth.gov/menstrual-cycle/your-menstrual-cycle
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6964059/
3. https://www.mayoclinic.org/diseases-conditions/premenstrual-syndrome/symptoms-causes/syc-20376780
4. https://www.mayoclinic.org/diseases-conditions/perimenopause/symptoms-causes/syc-20354666#:~:text=Perimenopause%20means%20%22around%20menopause%22%20and,start%20perimenopause%20at%20different%20ages.
5. https://www.mountsinai.org/health-library/report/menopause#:~:text=Perimenopause%20can%20begin%20in%20some,the%20length%20of%20the%20cycle.
6. https://my.clevelandclinic.org/health/diseases/21608-perimenopause#:~:text=Some%20people%20are%20in%20perimenopause,adjusts%20to%20different%20hormone%20levels.
7. https://www.mayoclinic.org/diseases-conditions/premenstrual-syndrome/expert-answers/pmdd/faq-20058315
8. https://www.acog.org/womens-health/experts-and-stories/the-latest/mood-changes-during-perimenopause-are-real-heres-what-to-know
9. https://www.nichd.nih.gov/health/topics/menstruation/conditioninfo/irregularities#:~:text=For%20most%20women%2C%20a%20normal,from%2021%20to%2035%20days.&text=However%2C%2014%25%20to%2025%25,other%20problems%2C%20like%20abdominal%20cramps.
10. https://www.nichd.nih.gov/health/topics/menstruation/conditioninfo/causes#:~:text=Menstrual%20irregularities%20can%20have%20a,%2C%20trauma%2C%20and%20certain%20medications
11. https://www.healthline.com/health/menopause/perimenopause-periods
12. https://www.healthline.com/health/menopause/perimenopause-periods#heavy-bleeding
13. https://www.mayoclinic.org/diseases-conditions/anemia/symptoms-causes/syc-20351360
14. https://www.menopause.org/for-women/menopause-faqs-hot-flashes#:~:text=have%20hot%20flashes%3F-,A.,they%20may%20never%20go%20away.
15. https://www.health.com/mind-body/brain-fog-is-it-pms-or-something-more-serious#:~:text=Brain%20fog%E2%80%94when%20you%20can,happen%2C%20such%20as%20hormone%20fluctuations.