Before we talk about the hormonal changes during menopause, it’s worth spending a little time on the role of hormones in the body. Hormones are the body's chemical signalers, coordinating and regulating everything from your metabolism, digestion, to sleep or how exercise impacts your body. In the same way that your nerves transmit electrical signals from your brain to muscles when you want to move your hand, organs such as your pancreas, thyroid or ovaries transmit chemical signals to communicate with other parts of your body.
Hormones that act as chemical signalers are part of what’s known as the endocrine system (this is where we get the word endocrinologist – a doctor who specialises in hormonal health). Oestrogen, progesterone, testosterone, thyroid hormone, insulin and cortisol are all examples of endocrine hormones. These hormones are released from glands and transported in your bloodstream to trigger changes in other parts of your body. These changes depend not only on the hormone but also what type of cell is triggered.
As you age, the quantity of hormones your body produces changes, which can impact all sorts of things. The chart above shows how some hormones can change in women over time. During perimenopause oestrogen levels start to fluctuate and eventually decreases. But though we often talk about oestrogen in relation to menopause (and its decline as the main culprit for menopause symptoms), other hormones also decline. Progesterone and testosterone decline, as does melatonin, which is a hormone that helps regulate our circadian rhythms - in other words, it affects our sleep patterns.
Understanding the role and far-reaching actions of hormones help us understand why during menopause so many bodily changes happen. To read more about the symptoms of menopause visit our symptoms section.
Catherine Whitlock & Nicola Temple, Meet your Hormones, Octopus Publishing Company