Menopause is normal, and every woman will have a menopause.
The words and definitions around menopause are often a bit confusing and used inconsistently, so to clarify I use the following terms.
Menopause terminology explained
We say that a woman’s last natural period is called her menopause. We have to wait one full year to be confident that this was her last natural period. So, if a woman’s last period was on the 17th July 2020 when she was 50, we say she is menopausal on 17th July 2021. The medical term is actually post-menopausal.
Her entire life from starting her periods until the menopause is called pre-menopause. So, using the same example above, while she was 14- 49 years old she will be pre-menopausal. Pre-menopausal women will have periods bar some exceptions e.g. pregnancy, gynaecological problems, medical intervention, a Mirena coil or certain medication.
Quite a lot of confusion comes with the term peri-menopause. This means the time around menopause, and we use it to describe the time when a woman begins to have symptoms but is still having periods. In the UK, this phase typically starts around the age of 42 – 43. So, a peri-menopausal women is still having periods and so will also be pre-menopausal.
The menopause happens because a woman’s egg store is depleted to practically zero. Eggs instruct the ovaries to release two ‘female’ hormones but which are of course present for men and woman alike – estrogen and progesterone. If there are no eggs, then the hormone levels will fall. A third hormone called testosterone does not require there to be eggs, but testosterone levels will fall after the menopause- more about this later.
A woman’s eggs are stored in the ovaries which sit in little bubbles of fluid called follicles. These follicles constantly release estrogen which rises and the falls during the menstrual cycle. Progesterone is released after egg release or ovulation.
Typically, this doesn’t just happen all of a sudden, and egg number and egg quality will gradually decrease as women age – particularly after the age of 37. The first sign of falling egg quality and number is a decrease in fertility and increase in miscarriage rates. Many symptoms will begin whilst a woman has periods in her 40s and starts peri-menopause. Biologically there is a reduction in the number of good quality eggs with the subsequent decrease in hormone levels.
The familiar menopausal symptoms are mainly due to a lack of estrogen, and so providing estrogen medication is the first and main building block of HRT. The female body has estrogen receptors in all sorts of places in the body. The brain and central nervous system, blood vessels, skin, hair follicles, bones, bladder, vagina and vulva. It’s not that surprising that a fall in estrogen causes wide ranging problems including mental, psychological, sexual and physical symptoms. Longer term depletion of estrogen can lead to osteoporosis and heart disease. Replacement of hormones can help prevent these changes and also possibly help prevent dementia.
Most symptoms will stop being significant within two to three years, but symptoms can last much longer. Many women will be able to deal with peri-menopausal symptoms with changes in lifestyle, diet and exercise but some women will want HRT. This is by no means the magic answer and unhelpfully there have been a lot of myths about HRT in recent years, and more than 50% of women who are offered HRT will not use it.
I think that a fall in fertility is the very first symptom of decreasing egg number and quality. The age-related fall in fertility rates was how I began my interest in menopause. I noticed that some women reported feeling really well when we were using hormone replacement before replacing frozen embryos. As the patients were experiencing declining ovarian function, the addition of hormones during fertility treatment provided symptomatic relief.
Ovarian function does not decrease at a predictable nor even rate and there will be intermittent episodes of normal and abnormal function in the peri-menopause. That’s why periods can stop for some time and then restart, leading to why symptoms can come and go.
Egg life cycle
We know that egg number falls with age, but it’s not widely known that the most number of eggs a woman will ever have is when she is about 24 weeks old in her mother’s uterus. At this point she has about 6 million eggs. This number falls rapidly and by birth she has 2 million eggs. When a woman starts her periods (called the menarche) she has only about half a million eggs. Leading up to this time women don’t have periods, so what happens to the eggs? The answer is that each and every egg has a pre-determined date to die or breakdown. So most eggs die without ever being ovulated – in fact only 0.5% of the initial number of eggs will ever be ovulated.
The automatic egg death will happen no matter what. Even if a woman was to never ovulate in her entire life (for instance she was on the pill all her life) she would still go through the menopause at the same age. Pregnancy and breast feeding are not protective in this regard.
It’s common that women ask for blood tests to confirm whether they are menopausal. The NICE guidelines suggest offering blood tests to women who are not yet 45 years old, but they do not suggest doing blood tests if a woman has peri-menopausal symptoms and is over the age of 45. The reason for this is that the ovarian function and hormone levels will be altered in almost all women who are 45 or older. If hormone levels are normal in peri-menopausal women, it does not mean that they have previously been normal or will be normal in the future.
We know it’s slightly contentious but having blood tests during HRT treatment is not necessary for the majority of women on HRT. Blood tests are sometimes useful when there are unexpected responses (over or under). Standard dosages of HRT do not need to be followed up with blood tests. The exception is testosterone, where a level should be checked every 3 or 4 months after starting treatment.
When will I have a menopause?
The average age of menopause (last period) in the UK is between 47 and 52 years old with an average age of 51, but symptoms may well start many years before. Some women will have a menopause before the age of 45, which we call an early menopause – but is still considered to be natural. An early menopause is managed in the same way as menopause in on older woman.
About 1:100 women will have a menopause before the age of 40, which is called Premature Ovarian Insufficiency (POI). This often comes out of the blue and can have a massive impact on a woman’s life. We generally are very keen on treating women with POI with hormonal support to prevent long term consequences of low estrogen – namely bone thinning and cardio-vascular problems. Without treatment, women with POI will sadly have a decreased life expectancy, so it’s really important to seek help and advice as early as possible.
There isn’t a way to precisely know when a woman will have her last period. Although blood tests and scans can give you information about your current hormone and follicle status, it’s really not possible to use investigations to predict. In fact, the best predictor is knowing when your mum had her menopause.
So in summary, menopause is natural but its effects can be challenging. Many women will have symptoms when they still have periods, others will be relatively symptom free. Everyone is different, and there are lots of different options to help should you need it.