Perimenopause Symptoms Explained: What’s Actually Happening to Your Body in Your 40s

If you’ve reached your 40s and suddenly don’t feel quite like yourself, perimenopause may be part of the explanation.

Perhaps your once-reliable period has become heavier or unpredictable. You’re waking at 3am for no obvious reason. Your anxiety has appeared from nowhere. You can’t remember why you walked into a room, your jeans fit differently despite eating the same way, or you’re wondering where your libido went.

These are some of the most common concerns I hear from women in my Hillarys clinic.

What is perimenopause?

Perimenopause is the transition leading up to menopause and can begin years before your final period. During this time, ovarian hormone production becomes increasingly variable. Oestrogen can rise and fall considerably, while ovulation may become less consistent, which changes how much progesterone your body is exposed to each month.

This hormonal variability helps explain why perimenopause can feel so unpredictable. You may feel perfectly well one month and completely unlike yourself the next.

Common perimenopause symptoms

• Heavier or irregular periods
• Difficulty sleeping or waking during the night
• Anxiety, irritability or mood changes
• Brain fog and poor concentration
• Hot flushes and night sweats
• Weight gain, particularly around the abdomen
• Fatigue
• Breast tenderness
• Headaches and migraines
• Vaginal dryness
• Reduced libido
• Muscle and joint aches

The good news is that there is so much we can do to support women through this transition.

Heavy periods in perimenopause: where has my progesterone gone?

One of the earliest changes women may notice during perimenopause is a change to their menstrual cycle. Periods may become closer together, further apart, lighter, heavier or simply unpredictable.

Some months, your ovaries release an egg as normal, and after the egg is released, the leftover structure produces progesterone for the rest of the cycle. But as your ovaries change through perimenopause, some months you might not ovulate properly at all, which means that progesterone boost doesn’t happen the way it used to.

Meanwhile, your oestrogen is still doing its thing, building up the lining of your uterus. Normally progesterone comes along and helps keep that lining stable. Without enough progesterone to balance it, that lining can build up more than it should, and that’s a big part of why periods become heavier or more erratic during perimenopause.

Chaste tree for progesterone support

One of the herbs I consider when the menstrual cycle is short and bleeding is heavy is chaste tree (Vitex agnus-castus). Vitex doesn’t actually contain progesterone itself. Instead, it works by gently nudging the hormonal signals your brain sends down to your ovaries, encouraging your body to produce its own progesterone more effectively. It has a long history of use in Western herbal medicine for PMS, irregular cycles and sore, tender breasts before your period.

Heavy bleeding should also never simply be assumed to be hormonal. Fibroids, adenomyosis, polyps, thyroid dysfunction and other gynaecological conditions need to be considered, and persistent heavy bleeding warrants medical assessment.

Heavy periods can also deplete iron stores, so ferritin and iron status is worth getting checked if you’re also feeling breathless, exhausted, getting restless legs at night, or noticing more hair falling out than usual.

Why does perimenopause cause anxiety and poor sleep?

You may have slept beautifully for decades and suddenly find yourself wide awake at 2am or 3am, or perhaps you’ve become inexplicably anxious, wired or overwhelmed despite nothing obvious changing in your life.

Your hormones have a much bigger effect on your brain than most people realise. Progesterone in particular breaks down into a compound that acts a bit like a natural calming agent in the brain, helping you feel settled and switch off at night. When progesterone drops or becomes unpredictable, as it does in perimenopause, that natural calming effect becomes less reliable too, which is part of why sleep and anxiety can both take a hit at the same time.

Of course, hormones aren’t the only reason women stop sleeping well in their 40s. Stress, alcohol, caffeine, blood sugar instability, hot flushes, sleep apnoea and simply having an overloaded brain can all contribute.

Start with your light environment

Before reaching for supplements, I like to get the basics right. Your brain uses light as one of its strongest signals for determining whether it should be awake or asleep. Try:

• Reducing bright overhead lighting after sunset
• Avoiding phones, laptops and tablets in the hour or two before bed
• Keeping your bedroom genuinely dark
• Wearing a comfortable sleep mask if ambient light is unavoidable
• Getting outdoor morning light soon after waking
• Maintaining reasonably consistent sleep and waking times
• Avoiding caffeine later in the day
• Minimising alcohol, particularly when night waking or hot flushes are a problem

Sometimes the least glamorous interventions are the most powerful.

Magnesium and L-theanine

Two nutrients I frequently consider for the wired-but-tired perimenopausal woman are magnesium and L-theanine.

Magnesium is involved in hundreds of processes in your body and plays an important role in keeping your nervous system and muscles working properly. The research on magnesium for sleep is a bit mixed, so I don’t think of it as a natural sleeping tablet. What it can do, though, is form part of a bigger sleep and stress-support strategy, especially if your intake has been low to begin with.

L-theanine, an amino acid naturally found in tea, is another useful option. Research suggests it may promote relaxation without acting as a sedative, and recent systematic research reviews have found improvements in several subjective measures of sleep. For the woman whose body is exhausted but whose brain refuses to switch off, this can be a genuinely useful nutrient to consider.

Perimenopause brain fog: why can’t I think anymore?

Walking into a room and forgetting why you’re there. Losing words mid-sentence. Reading the same paragraph three times. Feeling as though your brain has 27 browser tabs open simultaneously.

Brain fog is a recognised symptom of the menopause transition and there’s a real reason for it. Your brain actually relies on oestrogen. It plays a role in how your brain cells communicate with each other and how efficiently your brain uses energy, particularly in the areas responsible for memory and focus. So when oestrogen starts fluctuating during perimenopause, it makes sense that concentration, word retrieval and memory can wobble along with it. Sleep deprivation doesn’t help either.

Creatine isn’t just for the gym

One nutrient I’m increasingly interested in for women during midlife is creatine monohydrate. Most people associate creatine with bodybuilders, but the brain is an extraordinarily energy-hungry organ and it turns out creatine helps your brain cells generate energy quickly too, not just your muscles.

A 2024 systematic review and meta-analysis of randomised trials found that creatine supplementation produced improvements in memory and some measures of attention and processing speed. Creatine is also useful for supporting muscle, another increasingly important consideration as women move through menopause, which makes it an interesting nutrient because we’re potentially supporting both brain and muscle health at the same time.

Hot flushes and night sweats

Hot flushes are probably the symptom most strongly associated with menopause, but they can begin during perimenopause while you’re still menstruating.

Here’s what’s happening. Your changing hormones affect the part of your brain that acts like your body’s internal thermostat. During perimenopause, that thermostat becomes much more sensitive, so a tiny rise in your body temperature that you’d normally never even notice can suddenly trigger a full flush, with your body scrambling to cool you down through sweating. Cue throwing the doona off, then pulling it back on, then throwing it off again.

Sage for hot flushes

Sage (Salvia officinalis) is one of my favourite Western herbal medicines when heat and excessive sweating dominate the symptom picture. Clinical trials have looked at sage extracts for menopausal symptoms, and a review of that research found it can reduce how often hot flushes happen. This is a lovely example of a traditional herbal remedy starting to pick up solid modern evidence behind it.

Zizyphus for the woman waking hot and with night sweats

When night sweats and disturbed sleep occur together, I also consider Ziziphus spinosa (zizyphus). Known as Suan Zao Ren in Chinese medicine, it has traditionally been used for restless, disturbed sleep. A small clinical trial found it improved sleep quality, which backs up centuries of traditional use. For the woman waking hot, restless and unable to settle again, it can be a particularly useful herb within an individualised herbal formula.

Perimenopause weight gain: is it really my hormones?

One of the most common Google searches about perimenopause is some variation of “why am I gaining weight when I haven’t changed anything?” The answer is rarely simply “your metabolism has stopped.”

Midlife brings a whole cluster of changes at once: your body composition shifts, how your body handles blood sugar shifts, muscle mass tends to decline if you’re not actively working to keep it, sleep gets harder, stress hormones behave differently, and many women become less active without really noticing. On top of that, menopause tends to push weight specifically toward the abdomen. Then poor sleep makes blood sugar and appetite harder to manage, and unstable blood sugar makes sleep worse. It becomes a loop.

Rather than drastically restricting food, I generally start by changing what the meal is built around.

Prioritise protein

Protein becomes increasingly important through midlife. Aim to include a decent protein source at every meal: eggs, Greek yoghurt, fish, chicken, lean meat, tofu or tempeh, cottage cheese, legumes, or a protein-rich smoothie. Protein helps you feel fuller for longer, helps you hang onto lean muscle, and keeps your blood sugar steadier after you eat. Instead of asking “how little can I eat?”, I would rather women ask “where is my protein?”

Fibre is the other half of the equation

Vegetables, legumes, berries, nuts, seeds and whole grains all bring fibre to the table, which slows digestion down, feeds your gut bacteria, and generally makes a meal work better for your body. A simple goal is to make plants abundant and varied.

Pairing protein and fibre at meals is one of the simplest strategies I use for women dealing with afternoon energy crashes, sugar cravings, extra weight around the middle and disrupted sleep. Steadier energy through the day also makes it easier to exercise, make good food choices, and get to bedtime without being simultaneously exhausted and wired.

Breast tenderness in perimenopause

Breasts suddenly feeling swollen, heavy or painfully tender is another common complaint. Because oestrogen and progesterone can swing around so much during perimenopause, breast tenderness can show up even in women who never really experienced it before their period in earlier years.

I’ve written an entire article explaining the hormonal and nutritional factors involved in breast tenderness before your period: Why Do My Breasts Hurt Before My Period? The Science Behind PMS-Related Breast Pain.

New lumps, changes to your nipple, ongoing pain in one specific spot, or any other unusual breast symptom should always be checked by your doctor rather than put down to hormones.

Where did my libido go?

This deserves a much more compassionate conversation than simply saying “your hormones are dropping.”

By the time many women reach their 40s, they have spent years caring for children, working, running a household, remembering everybody’s appointments, supporting ageing parents, organising school, planning meals, and carrying an enormous invisible mental load. Then we wonder why spontaneous desire isn’t exactly top of mind.

Hormonal changes absolutely matter too. Lower or fluctuating oestrogen can cause vaginal dryness and discomfort, and on top of that, poor sleep, stress, certain medications, how you feel about your body, and what’s going on in your relationship can all affect your desire for intimacy. But sometimes the woman sitting in front of me doesn’t need to be told that her libido is broken, she’s just depleted.

This is where naturopathic medicine can be really valuable. Rather than treating low libido as its own isolated problem, we look at rebuilding your energy, your sleep, your stress resilience and your overall nutrition, because desire tends to come back once you’re not running on empty.

Shatavari, the herb of “100 husbands”

One of my favourite herbs in this context is the Ayurvedic herb Shatavari (Asparagus racemosus). Its traditional Sanskrit name is often translated as “she who possesses 100 husbands”, a wonderfully memorable nod to its traditional reputation as a tonic for women’s reproductive health and vitality.

Modern research is now catching up with that traditional use. Recent clinical trials in perimenopausal and menopausal women found improvements across a range of menopause symptoms, including stress, fatigue and hot flushes.

I don’t prescribe Shatavari because I expect anyone to acquire 100 husbands, one is usually enough, but I do use it when a woman needs rebuilding: when stress, depletion, hormonal change and a loss of vitality have all piled on top of each other. Sometimes bringing back the spark starts with helping the woman herself feel alive again.

Perimenopause isn’t just about hormones

If a 45-year-old woman comes to me with fatigue, anxiety, poor sleep, hair loss, weight gain and heavy periods, it would be easy to file all of that under “perimenopause” and stop there. But we shouldn’t.

In naturopathic practice I also check for:

• Iron deficiency, particularly if periods are heavy
• Thyroid function
• Vitamin B12, folate and vitamin D levels
• Blood sugar and insulin regulation
• Whether you’re getting enough protein and overall energy from food
• Chronic stress
• Gut and digestive health
• Alcohol and caffeine intake
• Whether any medications could be contributing
• Sleep apnoea and other sleep disorders
• Exercise habits and muscle mass

Perimenopause may well be the backdrop, but working out exactly what’s amplifying your particular symptoms is where personalised care really earns its keep.

You don’t have to just put up with perimenopause

Perimenopause is normal, but feeling terrible for years doesn’t have to be.

Natural medicine offers a broad toolkit during this stage of life: nutrition, herbal medicine, targeted nutrients, sleep strategies, exercise, stress support, and getting to the bottom of any nutritional or metabolic factors that might be making things worse.

And naturopathic care doesn’t have to sit in opposition to conventional medicine, either. Menopausal hormone therapy and other medical treatments can be very effective and appropriate for many women. Natural medicine can work alongside medical care, or offer an alternative for women who’d prefer a non-hormonal approach or can’t use hormone therapy. The goal isn’t to “perfectly balance your hormones”, because some fluctuation is just part of the biology of perimenopause. The real goal is helping your body cope with those fluctuations with a lot more resilience.

If you’re experiencing perimenopause symptoms and looking for naturopathic support in Perth, I work with women to understand the individual hormonal, nutritional, metabolic and lifestyle factors contributing to their symptoms.

References

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