How Hormones Affect Your Mood Across Your Cycle

Q: Why does my mood change at different points in my cycle?

Oestrogen and progesterone shape the brain chemicals behind your mood, including serotonin and dopamine. As these hormones rise and fall across your cycle, your mood, energy, and emotional sensitivity tend to move with them. You are most likely to notice the shift in the premenstrual phase, when both hormones drop, and at the start of your period, when oestrogen falls sharply.

Q: What is the difference between normal premenstrual mood changes and PMS?

PMS describes a pattern of symptoms, like irritability, anxiety, and fatigue, that show up in the one to two weeks before your period and ease once bleeding starts. Mild to moderate premenstrual mood shifts are a normal part of your cycle. PMS tends to describe times when those symptoms are more consistent or more noticeable, while staying manageable and not significantly disrupting your daily life.

Q: How do I know when cyclical mood changes are worth discussing with a doctor?

If premenstrual mood changes are affecting how you function at work, in your relationships, or in daily life, that is a good reason to speak to your GP. Tracking your mood and cycle for two to three months before the appointment gives your doctor useful information to work from. Your GP can talk through options including lifestyle changes, talking therapies your GP can refer you to, or medical treatment, depending on your situation.

Q: Does progesterone always have the same effect on mood?

Progesterone affects mood differently from one person to the next. It can work on GABA receptors in your brain in a way that feels calming, yet higher progesterone in the luteal phase can also leave some people with lower mood or more irritability. The sharp drop in progesterone just before your period can feed into mood swings too. Your own response may not match any single description.

Woman with black hair, sitting and leaning on a blue couch.

Bloume content relating to health, wellbeing and nutrition has been reviewed and validated by relevant medical professionals in the UK, based on UK guidelines and practices applicable at the time of publication. Recommendations in other localities may differ from those found on our site and you should always seek the guidance or advice of relevant healthcare professionals in your area.

Most people notice that how they feel changes across the month, sometimes in ways that are hard to explain. Those shifts in mood, energy and motivation tend to follow your hormonal cycle more closely than you might expect. Oestrogen and progesterone influence brain chemistry as well as the body, which is why the pattern often becomes easier to recognise once you know what to look for.

These two hormones rise and fall in a steady pattern across your cycle. They sway brain chemicals like serotonin and dopamine, so the shifts you feel in your mood, energy, and emotional sensitivity tend to follow that same rhythm. The link between your hormones, your mood, and your cycle becomes clearer once you can see what happens at each stage, and what counts as everyday variation.

Oestrogen, serotonin, and the first half of your cycle

How you feel from one day to the next is tied closely to your brain chemistry, and your hormones have a hand in that. Oestrogen and progesterone both shape the brain chemicals behind your mood, including serotonin and dopamine. Oestrogen in particular helps keep serotonin available, and since serotonin steadies your mood, the hormonal shifts across your cycle can genuinely change how you feel day to day.¹

In the follicular phase, the roughly two weeks from the start of your period to ovulation, oestrogen climbs steadily. As it rises, you may notice more motivation, clearer thinking, and a generally brighter mood. Energy often feels more available, and being social or active can feel easier during this stretch.²

When your period starts, oestrogen drops sharply. That drop can bring tiredness, low energy, and more emotional sensitivity in the first day or two. The physical side of your period and the hormonal dip often land together, which can make the start of bleeding feel heavier in mood as well as in body.³

Two women conversing in a room, one with her hair in buns and the other smiling.

Progesterone and the second half of your cycle

After ovulation, your cycle moves into the luteal phase. Progesterone rises here, and for some people that brings a sense of calm. Progesterone works on GABA receptors in your brain, the ones that help dial down stress and anxiety, and that may be part of the settling effect you notice.⁴

Higher progesterone in the luteal phase can also leave you feeling flatter, more sluggish, or more easily irritated. As this phase goes on and both oestrogen and progesterone drop sharply in the days before your period, mood swings can become more noticeable. How strongly it affects you will vary.⁵

Premenstrual Syndrome and what normal variation looks like

Premenstrual Syndrome (PMS) is the name for the cluster of physical and emotional symptoms, like irritability, anxiety, and fatigue, that show up in the week or two before your period and then ease once bleeding starts. PMS is a normal response to the hormonal shifts at the end of the luteal phase, and it is something many people recognise.⁶

Everyday cyclical mood change tends to be noticeable but manageable. It follows a pattern tied to your cycle, and it eases once your period arrives. You might feel more emotionally reactive, less motivated, or more tired during this window. These shifts can be uncomfortable, and they sit within the normal range of what your cycle produces.

When these mood changes are worth a closer look

For some people, premenstrual mood changes feel far more intense than this. If yours are severe enough to affect your daily life, your work, or your relationships, that can point to a stronger sensitivity to hormonal shifts than is typical. It is also worth knowing that an existing mental health condition can flare during the premenstrual phase, even when it is otherwise well managed.⁷

Tracking your mood and cycle

Tracking your cycle alongside your mood over two or three months can help you spot patterns and connect how you feel to where you are in your cycle. It is also useful information to bring to a GP appointment. When cyclical mood symptoms feel unmanageable, your GP can talk through a range of options with you, including lifestyle changes, talking therapies, or medical treatment. Noting when the mood changes start, what they feel like, and how long they last gives your GP a clearer picture to work from.⁸

Frequently Asked Questions

Why does my mood change at different points in my cycle?

What is the difference between normal premenstrual mood changes and PMS?

How do I know when cyclical mood changes are worth discussing with a doctor?

Does progesterone always have the same effect on mood?

Sources

[1] The relationship between hormones and mental health

Oestrogen and progesterone act as chemical messengers that regulate mood-critical brain neurotransmitters such as serotonin and dopamine.
[2] Estrogen and Women's Emotions

Oestrogen can boost mood by increasing the brain's levels of serotonin. During the follicular phase, rising oestrogen can correspond with increased motivation and better mood.
[3] How Your Menstrual Cycle Affects Your Mental Health

A sharp drop in oestrogen levels at the beginning of menstruation can lead to fatigue, low energy, and increased emotional sensitivity.
[4] How Progesterone Affects Your Mood, Sleep, and Energy

Progesterone can have a calming effect on the brain by interacting with GABA receptors, a neurotransmitter that helps reduce feelings of stress and anxiety.
[5] Untangling the links between wellbeing and the menstrual cycle

In the luteal phase, high levels of progesterone can be linked to feeling less happy and more irritable, while the sharp drop before a period can contribute to mood swings.
[6] How Your Menstrual Cycle Affects Your Mental Health

Premenstrual Syndrome (PMS) is a common condition where symptoms like irritability, anxiety, and fatigue appear in the week or two before a period and resolve afterwards, representing a normal response to hormonal shifts.
[7] How Your Menstrual Cycle Affects Your Mental Health

When cyclical mood changes are severe enough to disrupt daily life, work, or relationships, it may indicate a greater sensitivity to hormonal fluctuations. Existing mental health conditions can also be made worse during the premenstrual phase.
[8] How Your Menstrual Cycle Affects Your Mental Health

If cyclical mood symptoms feel unmanageable, seek support from a GP. Tracking your cycle and mood can provide valuable information for your doctor, who can explore options like lifestyle changes, talking therapies, or medical treatments.