Periods 101
Written By
Share with others
Perimenopausal hot flushes – how do they feel and why do we get them?
It’s getting hot in here
If you’re already experiencing them then you don’t need me to tell you that hot flushes are a swift and exaggerated way of dissipating heat. If you aren’t experiencing them, then buckle up because you’re likely to. Hot flushes are the most well-known menopausal symptom and for good reason – in Western countries, up to 88 per cent of us will experience them. This number does vary and can be as low as 9.5 per cent in Japan, though that particular study was conducted in 1984 and a more recent study found the rate to be 36.9 per cent, which is still lower than that of Western countries.
Their frequency can vary hugely too. Some people will have as few as five per year and others will experience as many as 50 per day, with individuals also experiencing variations in how long they last – the duration of hot flushes has been reported as generally being between one to five minutes, though some can last up to an hour.
As a feature of both perimenopause and postmenopause, hot flushes and night sweats can persist in the years following your last period. In the Study of Women’s Health Across the Nation, which studied 3,302 US women undergoing the menopause transition, the average duration was 7.4 years. At the age of 65, 25 per cent of us will still be experiencing them. In one study of women aged 85, around 16 per cent were still experiencing hot flushes and almost 10 per cent of these women were still moderately or very distressed by them.
What each person experiences will vary, but typically hot flushes feature a sudden sensation of heat which is often accompanied by sweating and reddening of the skin. As well as the sense of heat, hot flushes can be accompanied by dry mouth, palpitations, an adrenalin rush, breathlessness, dizziness and nausea. They can occur spontaneously or in response to changes in environmental temperature, stress, emotions such as embarrassment and shame, or drinking caffeine, alcohol and warm drinks. Here’s how some of my clients described their flushes:
‘Heat that radiates from my chest and tingles. I have to stop whatever I’m doing and take some clothes off or I start to feel sick.’
‘It’s like molten lava rampaging through you with nowhere to go, followed by having a cold bucket of water chucked over you.’
‘The heat swallows me up, like being on fire from the inside out.’
‘The combination of heat and panic makes me feel like I’m trapped in a furnace’
But they can also feel milder, like someone’s turned the central heating up a notch or hot prickles on your chest and back:
‘You know the sudden flush of heat that you get when you feel embarrassed? It’s a bit like that.’
‘I feel hot and have to take a layer of clothing off, then five minutes later I have to put it back on again, and that’s basically how I spend my day – taking my sweater on and off. I’d rather that than what some of my friends are going through though.’
Hot flushes can have a tremendous impact on the personal and professional lives of those experiencing them, and the consequences of them are often underestimated. Not everyone will view them negatively though. My friend Val swears they’re the reason she lost weight during her transition and she told me that her skin looked incredible. Plus, she loved accessorising with beautiful fans and her heating bill plummeted.
Risk factors for developing severe hot flushes include:
- Surgical menopause
- Obesity
- Smoking
- Childhood neglect or abuse (the impact of abuse continues long after it has stopped)
- Prior anxiety or depression
- History of taking the oral contraceptive pill.
Despite their prevalence and impact on quality of life, the underlying mechanism that results in a hot flush remains unknown. Although hot flushes are associated with the lower levels of oestrogen that accompany the later stages of the menopause transition, they can also occur prior to the withdrawal of oestrogen, so the explanation of a low oestrogen state is inadequate.
I hesitate to include a study that’s almost as old as I am, but this one is often referenced in more recent research papers because it could find no relationships between the presence of hot flushes and the levels of oestrogens in blood, urine or the vagina – surprising, right? The same study also found no differences in the levels of oestrogen between those who have hot flushes and those who don’t. We also know that a drug called clonidine can reduce hot flushes but that it doesn’t raise oestrogen levels, which gives further weight to the idea that hot flushes aren’t about low oestrogen. What does differ are the levels of activity in a part of the brain known as the central noradrenergic system (CNA) and it’s the discovery of these changes that has led to the leading hypothesis of why we get hot flushes.
Your body is skilled at maintaining a core internal temperature of around 37°C, regardless of what the external temperature is up to. Most of the time, you can regulate your internal temperature without much effort. If the room you’re in is hot, your body will direct blood flow to your skin in order to get rid of heat and maintain its core temperature, whereas if the room you’re in is cool, your blood vessels constrict in order to minimise heat loss (this is why some skin tones will pale in cooler temperatures). When your body maintains its core temperature like this, it’s in a thermoneutral zone, i.e. the range of temperatures that you can maintain a normal body temperature at without using energy beyond your basal metabolic rate, which, for simplicity’s sake, we’ll call what your body can do whilst resting. If more activity is required in order to regulate your temperature, such as shivering when you’re cold or sweating when you’re hot, then you move beyond your thermoneutral zone.
Changes to this process of thermoregulation are what’s thought to result in symptoms such as hot flushes and night sweats. During the menopause transition, the thermoneutral zone narrows and when the upper threshold is crossed, a signal is sent out to get rid of heat. Wanna take a guess at how it accomplishes this? By dilating your blood vessels and increasing blood flow to your skin. And sweating, lots of sweating. In other words, your body has to do more in order to regulate your temperature.
Depressed mood and anxiety are strong predictors of hot flushes during the menopause transition. Those with moderate to high levels of anxiety experienced three to five times greater frequency and severity of hot flushes when compared to those who had lower levels of anxiety. This begs the question, do anxiety, depression and stress trigger hot flushes or is it the other way around? As you might imagine, it’s one of those relationships that goes both ways; feeling anxious can precede a hot flush and if you have a hot flush, it can cause you to feel anxious.
Buy Maisie’s book:
Perimenopause Power by Maisie Hill is out now. For tips on how to stay cool, and many more insights, get the book at Bookshop.org. The book was published by Bloomsbury Publishing PLC.
Did you know that the Mooncup menstrual cup is great for managing your periods during perimenopause? The Mooncup holds three times as much as a tampon, making it great for heavy days. And, because it’s non-absorbent, it won’t cause dryness when your period’s light. As you only need one Mooncup, you can always have it to hand, no matter how unpredictable your period may become when entering perimenopause. The measurement markings can also help you to monitor the changes in your flow. Buy yours today.
