Low energy in women

Disclaimer: Human Health is not recommending any specific medical treatment for any particular symptom, nor providing any other medical advice. Always seek the advice of your doctor regarding any medical concern.

Feeling low in energy can be extremely frustrating – doesn’t your body know that you’ve got things to do, and need energy to get them done? Decreased energy levels can be caused by a variety of different factors, but in this article we’ll focus on a couple of causes that affect women in particular.

Thyroid problems

The thyroid is a gland in the neck that produces hormones. These hormones are responsible for regulating the metabolism, or how the body stores and uses energy. According to the American Thyroid Association, 1 in 8 women will develop a thyroid disorder at some point in life, and women are 5–8 times more likely to be affected by thyroid problems than men.

Hypothyroidism is a condition that involves lower production of thyroid hormones compared to normal. People with hypothyroidism may feel fatigued or sluggish because the decreased levels of thyroid hormones slow down the metabolism.

Hyperthyroidism is the opposite of hypothyroidism, in that it involves increased production of thyroid hormones compared to normal. Higher levels of thyroid hormones can lead to symptoms such as anxiety, irritability, and insomnia, which may make it harder for us to sleep and feel rested, leading to feelings of low energy.

Iron deficiency anemia

Iron deficiency anemia is a condition that develops as a result of low iron levels in the blood. Iron is essential for oxygen transport around the body. Without iron, our cells and tissues don’t receive enough oxygen, which can affect their ability to function properly.

Because of the lack of iron and subsequent effects on oxygen transport, our body doesn’t produce enough energy which can leave us feeling tired and fatigued.

The American Society of Hematology reports that women, particularly those who menstruate, breastfeed, and are or have recently been pregnant are at higher risk of developing iron deficiency anemia.

Premenstrual syndrome

The menstrual cycle consists of four phases: The follicular phase, ovulation, the luteal phase, and menstruation.

During the luteal phase, some women experience a cluster of symptoms that is known as premenstrual syndrome (PMS). Some of these symptoms include irritability, changes in appetite, breast tenderness, and fatigue.

Fatigue during the luteal phase may be due to certain hormonal changes. At this point in the cycle, the activity of a hormone called estrogen decreases in the brain. This leads to the release of another hormone called norepinephrine. Norepinephrine decreases the activity of certain chemicals in the brain that affect our mood and behavior, including serotonin, dopamine, and acetylcholine.

Decreases in the activity of these chemicals in the brain may be responsible for making us feel sluggish and irritable.


The process of pregnancy can put quite a bit of physical strain on the body, and as such it’s no wonder pregnancy can cause feelings of exhaustion.

Pregnancy involves growing a whole human being – which requires the body’s cells and organs to use a lot of energy. The body systems are working overtime to both create new life, and maintain the health of the birthing parent at the same time.

In the early stages of pregnancy, major hormonal fluctuations as well as an increase in the volume of blood circulating in the body can induce feelings of fatigue.

As the pregnancy progresses, the physical energy required to support the growing child also increases, leaving the parent feeling drained and exhausted.

Furthermore, difficulty sleeping during and after pregnancy can contribute to feeling unrested and low in energy.


The National Institute of Mental Health has reported that more women are diagnosed with depression (10.3%) compared to men (6.2%).

In depression, the level of certain chemicals in the body and brain are imbalanced. Some of these chemicals, including serotonin and dopamine, are active in processes such as regulating, mood, behavior, attention, and energy levels.

If the level of these chemicals are too low in the brain, it may lead to feelings of fatigue and sadness.

Trying to figure out what’s causing your fatigue?

Feeling tired and fatigued may affect the ability to focus or remember things accurately, which could pose a challenge when it’s necessary to recount your experiences at an appointment.

To make sure you have all the information you need to provide your doctor with an accurate picture of how fatigue is affecting you, you might like to use a health tracking app.

Human Health is a free mobile app that can help you keep a record of your symptoms and treatments, and provide your doctor with a comprehensive overview of your health journey, from your current concerns to how your symptoms have changed over time.

We hope you found this article helpful. If you know someone who might benefit from learning about common causes of fatigue in women, please share this with them! We’d love for our resources to reach those who need them.


  1. American Thyroid Association.
  2. UpToDate. Patient education: Hypothyroidism (underactive thyroid) (Beyond the Basics).
  3. UpToDate. Patient education: Hyperthyroidism (overactive thyroid) (Beyond the Basics).
  4. American Society of Hematology. Iron-Deficiency Anemia.
  5. Pratyusha R. Gudipally; Gyanendra K. Sharma. Premenstrual Syndrome. In: StatPearls. July 2023.
  6. Fatigue in Pregnancy. Common Discomforts of Pregnancy. International Journal of Childbirth Education. 32:1. January 2017.
  7. National Institute of Mental Health. Major Depression: Statistics.
  8. Peacock BN, Scheiderer DJ, Kellermann GH. Biomolecular aspects of depression: A retrospective analysis. Compr Psychiatry. 2017 Feb;73:168-180.

Olivia Holland
Medical Writer