Perimenopause vs Menopause: What's the Difference and Why It Matters
So if you have begun to notice symptoms in your body and have done a bit of reading on the matter, you may have heard of or read about perimenopause and menopause. These terms are often used interchangeably and, while this is not surprising, it’s also not exactly accurate. They’re related, but they are not the same and it does matter if we’re all aware of the difference, both for getting an accurate read on where you’re up to with your own experience and for being able to have correct discussions with your doctor.
In this post I explain what both terms mean and what the key differences are between the two stages in terms of hormone changes, symptoms, duration and stages: Perimenopause vs Menopause. And why it is important to know what stage you are at.
There’s a spoiler coming ahead, but most of the changes that women experience and struggle with happen in the period before menopause, during perimenopause. Yet, the perimenopause gets by far the least attention.
There is a clear definition of menopause. It’s the moment in time when a woman has passed 12 months uninterrupted without a menstrual period, for unrelated medical reasons. That is it. Menopause is, in fact, a single point in time – a threshold that is reached when a certain amount of time has elapsed since your last period.
It can be diagnosed retrospectively. You don’t know you have gone into menopause until you have already been clear of periods for a year. That means your last period is then your menopause date.
The average age for natural menopause in Australia is 51 to 52 years, but this can happen from the mid-40s to mid-50s. Occurrence of menopause before the age of 45 is called early menopause and before 40 is premature menopause, and each requires particular medical attention.
Once we know you’ve experienced menopause, what comes next is the postmenopause. This is called the remaining years of a woman’s life after she has completed her child-bearing years.
Perimenopause (also known as the menopausal transition period), is the period of time before a woman has menopause. It’s the period from when the hormone production of the ovaries becomes less reliable to when menopause is known (12 months after the last period).
Perimenopause literally means “around menopause”; that’s another good way to conceptualise it. It is the run-up to the endpoint.
Perimenopause usually heralds the mid-to-late 40s in women, but sometimes even the early 40s or late 30s. It lasts on average four to six years, but is sometimes as short as a several months and as long as a decade or longer. It is indeed variable.
It’s during this period where the changes to endocrine (hormonal) levels are most apparent, and where most of the symptoms that women often associate with the experience of “going through menopause” occur.
Understanding the hormonal picture helps explain why perimenopause and menopause feel different.
During perimenopause, oestrogen and progesterone levels don’t just decrease in a linear fashion. They really don’t die a linear death. In some cycles, oestrogen peaks can be higher than average, but in other cycles oestrogen can be very low. As ovulation becomes irregular, progesterone levels become erratic.
In fact, it’s because of this variability that many of the most bothersome symptoms are generated during perimenopause. The brain and body are used to a relatively consistent levels of hormones throughout the cycle, and this becomes less consistent as we enter perimenopause. These inconsistencies can have a profound effect on menstrual irregularity, mood changes, sleep disturbance, anxiety and flushing (to name a few).
The term menopause refers to the point when a woman’s periods have stopped for 12 consecutive months, but an internationally recognised classification system for reproductive ageing called the Stages of Reproductive Ageing Workshop (or STRAW+10 for short), provides more precise classifications of the perimenopause based on cycle length and hormonal data. Early perimenopause consists of sustained cycle irregularity, while in late perimenopause the length of the gap between cycles increases in the lead up to the final menstrual period, or FMP.
Once menopause is established the nature of hormone excursions changes. This means low levels of oestrogen and progesterone without fluctuation. The ovaries no longer release an egg and fluctuate up and down in hormonal activity.
This cessation actually provides some women with a lift from some of the worst acute symptoms – particularly the severe mood shifts and irregular periods that can occur during perimenopause. But postmenopause, with its permanently low levels of oestrogen, does pose health risks which we will talk about shortly.
But this is where the distinction gets particularly practical. The symptoms aren’t strictly the same in perimenopause and postmenopause, but there is plenty of overlap.
Perimenopause is defined by its hormone imbalance and this is where the symptoms lay:
There are also some symptoms that continue into postmenopause:
Third-Phase Manifestation of Cardiovascular Disease: Postmenopause, oestrogen’s positive effects on the cardiovascular system, vegetative function and libido wane, leading to an increased risk of cardiovascular disease.
A side effect of the perimenopause-menopause distinction is diagnosis can be difficult. Now that menopause can only be diagnosed retrospectively after those 12 months without a period. But there is no beginning point to perimenopause, where most of the symptoms and trouble sits.
Frequently women ask, “can perimenopause be diagnosed by a blood test?” The answer is a definite “not always”, and “not by itself”.
During perimenopause, the hormones that stimulate the ovaries (follicle-stimulating hormone, or FSH) increase as the ovaries become less responsive. Elevated FSH levels imply perimenopause, but as FSH levels fluctuate during this period, it may not be reliable to make this diagnosis on the basis of one test. It may be normal in some cycles and abnormal in others.
In women over 45, clinical guidelines, including those of the Australasian Menopause Society, infer the condition of perimenopause from symptoms and menstruation history, rather than testing. Tests may be useful in women aged under 45 years to exclude premature menopause.
For women on hormonal contraception, such as the combined and progestogen-only pill, hormonal intrauterine device (IUD) or hormonal implant, it may be harder to tell if they are in perimenopause because contraception can change the menstrual pattern and some symptoms.
This does not mean that women contracepting are lacking perimenopause – it merely makes recognition more difficult. Women in this predicament who suspect perimenopause, should bring this up with their doctor for clarity on interpretation.
Whether you are experiencing perimenopause or the menopause is not just about labels. It has meaning for your health care.
This is a highly important, and often poorly understood, implication. Perimenopause does not mean you’re infertile. Eggs are still releasing from the ovary, but are less likely to be released regularly. You can therefore get pregnant until menopause. бриAustralian guidelines are now to continue with contraception for two years after the onset of amenorrhoea (cessation of menstruation) if the onset occurred before the age of 50 and for one year if after 50.
Quite a few unintentional pregnancies occur in women in their 40s who think they are too close to menopause to have babies. This presumption may be wrong – and costly.
These management strategies may be slightly different for the unstable-oestrogen fluctuations of perimenopause versus the stable-low-oestrogen milieu of postmenopause. Managing the symptoms of perimenopause may involve medications or approaches that should not be continued or changed in postmenopause and vice versa.
For instance, the complications of heavy menstrual bleeding, for example, are specific to the perimenopause. On the other hand, management of genitourinary atrophy, which is more common in postmenopause, may not have even crossed your mind while in perimenopause.
Long-term health risks tend to shift as women become postmenopausal. Indications for a DEXA bone density scan, cardiovascular assessment, blood pressure, cholesterol and blood glucose all take on greater importance from menopause.
There’s a baseline for these sorts of questions that is established by knowing you have passed menopause, as opposed to being in perimenopause.
The following chart offers a basic comparison of these two phases along a number of different fronts.
Menopause: Retrospective diagnosis after 12 months of amenorrhoea
It’s not necessary to wait until your symptoms are debilitating to go to your GP about perimenopause or menopause. It’s actually much better to talk about it sooner rather than later so strategies can be applied proactively.
It is worth booking an appointment if:
It’s important to consider that the discussion with your doctor is most helpful when you are able to provide information compelling enough to include description of both your symptoms but also a pattern of when the symptoms occurred, how frequently, what makes the symptoms worse or better and how they are disrupting your life. Keeping a diary of symptoms over a period of weeks can be very helpful in a consultation.
Postmenopause does not mean medical care stops, but rather this phase of life begins. Knowing you are postmenopausal, as opposed to menopausal, is helpful as now attention can be directed away from challenge of managing waxes and wanes of sex hormones and more to the issue of long term care in a low oestrogen environment.
The great news is that after perimenopause comes the self-reported improvement of postmenopausal health. The hormones of perimenopause, which fluctuate and create moods, cycles, and symptoms, become more stable. For those women that experienced an unpleasant perimenopause, postmenopause may be a welcome respite.
What won’t change is the need to have an up-to-date medical check, to stay active and well-nourished, and to have a doctor who is aware of the features of the postmenopausal state and who can advise you accordingly.
Perimenopause is not menopause although they go hand in hand. Perimenopause is the years-long transition period of fluctuating hormones, erratic periods and many symptoms. Menopause is the point when transition has ended. Everything after is postmenopause.
And the difference impacts how symptoms are considered, fertility managed, treatment strategies applied and periodic health assessed. Understanding what stage you’re at helps to guide health decisions.
If you are unsure of which stage you are at and what you are experiencing is far from clear-cut, this is normal. Transitions are not necessarily smooth. Speaking to a healthcare practitioner about your symptoms and cycle history, is always a good idea.