From understanding what they are, to what they do & what you can do to help keep them in balance, here’s the ultimate guide to your hormones

Hello, and welcome to the fascinating world of hormones. From sleep to metabolism and sex drive – you name it, they’ll probably affect it. But despite playing such a big role in so many things, we don’t always understand how important they are or what they do. 

Whether they’re stabilising our moods, or influencing how our menstrual cycle is going to go down each month, these chemical messengers can have far-reaching effects – physically and emotionally. So, with the aim of making your hormones a little easier to make sense of, we’re bringing you our go-to guide. Whether you’re wondering what they are, what they do or what can happen if they aren’t quite behaving how they should, find the answers to some common questions here. 

The most common questions about hormones

1. What are hormones?
2. What do hormones do in my body?
3. What is the role of hormones?
4. What hormones are responsible for what function?
5. What are the types of female sex hormones?
6. How can hormones change during the menstrual cycle?
7. What physical and emotional changes come with fluctuating hormone levels?
8. What happens if our hormones aren’t behaving?

1. What are hormones?

Put simply, hormones are chemical messengers that travel in the bloodstream to tissues and organs. 

2. What do hormones do in my body?

So, we’ve nailed what hormones are, but what do they actually do in our bodies? Consider the endocrine system as one big monitor; the hormones are chemical messengers with some influencing many functions in the body and others only a small number. The aim? To keep things balanced. These chemicals help coordinate our body’s functions, from metabolism to growth and development, as well as emotions, mood, sexual function and sleep.  

3. What is the role of hormones?

Their role is to provide an internal communication system between cells located in distant parts of the body, with the purpose of affecting certain processes, including:

- Mood
- Metabolism
- Growth and development
- Sexual function
- Reproduction

4. What hormones are responsible for what function?

Female sex hormones include:

Although it’s also present in men, oestrogen is the major female sex hormone. Not only does it play a huge role in regulating a woman’s reproductive function and monthly menstrual cycle, it also helps maintain bone density and certain levels may affect mood. We’re talking about the ultimate multitasker. 

This serves a very important role in fertility and early pregnancy. Despite being thought of as a female hormone, males also need progesterone to produce testosterone.


Libido, sex drive, sexual desire… whatever the vibe, testosterone plays a role in it. Although testosterone is considered a male sex hormone, women produce a small amount of it in their ovaries. It plays an important part in helping the body produce oestrogen and contributing to muscle and bone mass.

5. What are the types of female sex hormones?

Oestrogen and progesterone are the two main female sex hormones. There’s also the luteinising hormone (LH), which is made in the pituitary gland and helps stimulate ovulation, as well as the follicle stimulating hormone (FSH), which helps the ovaries function as they should.

6. How do female hormones change during the menstrual cycle

Hormones and the menstrual cycle. There’s a lot to grapple with. Let’s help you get to grips with the basics:

- The menstrual cycle can be broken down into three main phases – follicular (before the egg is released), ovulatory (as the egg is released) and luteal (after the egg is released).

- The follicular phase begins on the first day of menstrual bleeding and lasts until ovulation. At this stage, levels of oestrogen and progesterone are low, meaning the top layers of the uterus are shed and menstrual bleeding occurs. This bleeding lasts for an average of five days.

- Around this time, FSH levels increase slightly, which the pituitary gland starts to produce in response to low levels of oestrogen and progesterone, kick-starting the growth of several follicles in the ovaries. Later in the phase, as the FSH level decreases, one of these follicles will continue to grow and produce oestrogen, preparing the uterus – which is getting thicker in preparation for a fertilised egg to be implanted – for the next phase.

- Next up is the ovulatory phase, which usually lasts between 16 and 32 hours. This phase begins with an increase in LH levels and ends with the release of an egg, which can be fertilised for up to 12 hours after its release. During this phase, some women experience pain in their abdomen – hot water bottles at the ready. 

- And last (but by no means least) comes the luteal phase, which tends to last around 14 days (unless fertilisation occurs). During this phase, progesterone and oestrogen levels are high, which can sometimes cause breast swelling and tenderness. If the egg isn’t fertilised, levels of oestrogen and progesterone will decrease and a new menstrual cycle will begin.

7. What physical & emotional changes come with fluctuating hormone levels?

Changes in your body’s hormone levels before your period can cause a whole bunch of physical and emotional changes, including feeling bloated, breast tenderness, mood swings, feeling irritable, getting spots or greasy skin, and losing your sex drive. These changes are most commonly known as premenstrual syndrome (PMS) and symptoms tend to improve once bleeding begins. 

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8. What happens if your hormones aren't behaving?

Excessive exercise, stress, oral contraceptives, poor diet – these are just a few things that can result in a hormonal imbalance. As the name suggests, when you have a hormone imbalance, you have too much or too little of a certain hormone.

Women may experience an hormonal imbalance as they enter perimenopause (the transition towards menopause) and menopause (when a woman’s ovaries stop producing as much oestrogen and no longer release an egg each month). The reduced level of oestrogen can result in a lowered sex drive, hot flushes, night sweats, low mood or anxiety, difficulty sleeping and vaginal dryness – oh, the joys. If you’re experiencing these symptoms, it’s important you don’t suffer in silence. There’s a range of things you can do to try and improve symptoms initially, including cognitive behavioural therapy, which can help with low mood and anxiety, maintaining a healthy weight by eating a healthy, balanced diet and exercising regularly. If these don’t work, speak to your GP or you might want to consider the Boots Online Doctor Menopause & HRT Treatment service*, which can provide advice on how to manage symptoms and prescribe treatment where appropriate.

The takeaway

Hormones can be complicated, but you can stay in tune with your body to better understand what’s going on, and always seek advice from your GP if you’re worried – they’ve got your back. 

*Access to treatment is subject to an online consultation with a clinician to assess suitability. Charges apply