Atypical levels of chemical messengers in the brain can cause mood changes. Hormonal causes include abnormal levels of estrogen, progesterone, thyroid hormones, and cortisol.

If a person experiences mood changes before their menstrual cycle, during pregnancy, after childbirth, or in perimenopause, hormones may be the cause of those changes.

However, many factors can affect mood, and a doctor’s evaluation may be necessary to determine the underlying cause.

This article discusses mental and hormonal causes of mood changes and how to tell the difference. It also examines how to manage moods and what questions to ask a doctor.

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A large number of factors can cause changes in a person’s mood.

Every day, a person will experience mood changes due to ordinary events. For example, a compliment from a boss about work can lift a person’s spirits, while getting stuck in traffic can cause frustration.

Major life events can also have a significant effect on mood. For example, the death of a loved one can lead to depression, and losing a job can lead to anxiety.

Lifestyle factors may play a role as well.

A 2020 review notes that a healthy diet can reduce the risk of depression, and a 2018 review states that insufficient sleep may make people more sensitive to stressful events. Exercise is another factor that can boost a person’s overall mood.

Additionally, certain medications and physical health conditions can influence mood.

Atypical levels of neurotransmitters in the brain can affect emotions. Neurotransmitters are chemical messengers that enable communication between nerve cells.

Neurotransmitter levels outside the usual range can cause significant changes that may contribute to mood disorders.


While a range of factors may contribute to depression, low levels of neurotransmitters are one possible cause. The following neurotransmitters are involved in depression:

  • serotonin
  • norepinephrine
  • dopamine
  • gamma-aminobutyric acid

Bipolar disorder

Bipolar disorder is a mental health condition that involves shifts in mood and activity. A combination of factors may lead to this condition.

One such factor is an imbalance in neurotransmitters — particularly serotonin and dopamine — and the signaling systems within cells that regulate mood.

The following are possible hormonal causes:

Changes in reproductive hormones

These changes may occur at certain times of life.

Before a menstrual cycle

Up to 2 weeks before a menstrual cycle, some people may experience mood changes such as anger, anxiety, irritability, and low mood. This is called premenstrual syndrome (PMS)

When the symptoms are severe, the condition is called premenstrual dysphoric disorder. While researchers do not know the cause, changes in reproductive hormones may play a role.

During pregnancy

Changing levels of the reproductive hormones estrogen and progesterone can cause mood changes during pregnancy, especially in the first trimester. Some people may experience this moodiness for a limited time, while for others it may occur throughout pregnancy.

After childbirth

It is relatively common to experience the “baby blues” after giving birth. But for some people, the symptoms intensify and persist, leading to a condition called postpartum depression.

Within 2–3 days after childbirth, some people feel:

  • depressed
  • upset
  • anxious

While nonhormonal factors can cause these feelings, the sharp decline in estrogen and progesterone levels after childbirth likely plays a role.

During perimenopause and menopause

People are especially susceptible to depression during perimenopause and the years immediately after menopause.

Perimenopause is the period in which the body transitions from having a monthly menstrual cycle to menopause, the time when the monthly cycle stops. The hormonal shifts that happen during this time increase the risk of depression.

Low thyroid hormones

The thyroid gland produces several hormones that can affect mental health.

When levels of the hormone triiodothyronine (T3) are low, a person may experience anxiety and depression. And when T3 levels increase, so do levels of serotonin and norepinephrine, which are often deficient in anxiety and depression.

High cortisol levels

Cortisol is known as the stress hormone. Under typical circumstances, the body produces steady levels of cortisol.

However, according to a 2021 review, the body makes much more cortisol during stressful events. This can cause:

  • depression
  • irritability
  • emotional lability (the tendency to experience quick shifts in emotions)

If mood changes happen during times that involve shifting levels of estrogen and progesterone, it may suggest a hormonal influence. However, hormones are not necessarily the cause.

Because multiple factors can affect mood, a person may need a doctor’s evaluation to find out whether the cause is mental or hormonal.

The National Institutes of Health recommends the following self-care practices to promote mental health, which can help people manage their moods and emotions:

  • Engage in regular exercise: A mere 30-minute walk every day can enhance mood.
  • Get enough sleep: Aim to follow a sleep schedule. And reduce exposure to electronics before bed, as the blue light can interfere with sleep.
  • Eat nutritious meals and drink enough fluids: Eating nutritious foods and drinking plenty of water can increase focus.
  • Stay connected: Maintain a support network of family and friends.

A person may consider asking these questions:

  • Will my mood symptoms go away?
  • Do my mood symptoms indicate that I have a mental health condition?
  • What non-medication interventions do you recommend?
  • Do I need treatment? If so, how long will it take to work and what are the side effects?

Changes in mood may stem from mental or hormonal factors.

Atypical levels of neurotransmitters, estrogen, progesterone, thyroid hormones, and cortisol may contribute to the changes.

Mood changes may also result from everyday events, as well as some medications, health conditions, and lifestyle practices.

Healthy lifestyle practices such as exercising regularly and getting enough sleep can help people improve their mental health and manage their moods.