Why is IBS more common in women?

by

Although many gastrointestinal and mental health disorders seem to affect primarily women, the research into the reasons why is more or less vague. Women’s pain and other symptoms are often overlooked or considered exaggerated by their relatives and medical professionals. IBS is not an exception to this ‘rule’. There are several possible reasons why IBS is more common or often more severe in women.

Women are more likely to develop anxiety

It is now known that anxiety and stress may lead to IBS development. Women are generally more likely to develop an anxiety disorder throughout their lifespan. Similarly, women with IBS are also more at risk of having anxiety or depression associated with IBS. Female sex hormones can modulate stress response which could be the reason why women tend to respond to stress more intensely. It was found that cortisol, a hormone that helps regulate stress response, is released in greater quantities in male rats compared to female rats. This suggests that something similar happens in humans which would explain why women’s stress response is often stronger. (4.)

The menstrual cycle causes changes in IBS symptoms

In women, IBS more commonly occurs in the late teens to mid-forties which suggests that menstruation might play a role in the development and severity of IBS symptoms. About 40% of women reported changes in their IBS symptoms during the menstrual cycle. During the period week, hormone levels fluctuate which can lead to gastrointestinal symptoms such as abdominal pain, bloating, altered bowel habits, etc. (2.) Diarrhea seems to be the most reoccurring IBS symptom during menstruation, even though IBS-C is generally more common in women. It could be caused by:

  1. Release of prostaglandins – hormone-like substances that help release uterus lining (endometrium) out of the uterus and thus produce period. Prostaglandins stimulate gastrointestinal motility (movement of food through the digestive tract) and potentially lead to diarrhea.
  2. Progesterone (female sex hormone) leads to decreased gastrointestinal motility. In response to the reduction in progesterone levels during menstruation, gastrointestinal motility increases which could explain why diarrhea occurs more often. (3.)

Endometriosis could cause IBS

Some studies have found an increased risk of IBS in women with endometriosis. Endometriosis is a chronic inflammatory disease characterized by the presence of tissue resembling endometrium outside of the uterus. Common symptoms of endometriosis include:

  • abdominal pain
  • menstrual cramps
  • pain during or after sexual intercourse
  • fatigue
  • depression or anxiety

IBS and endometriosis are often misdiagnosed and due to this correct treatment is delayed. It is also not known whether endometriosis causes IBS or vice versa. (1.)

Are IBS symptoms worse in women?

A rapid increase in estrogen is associated with increased pain sensation

Although the actual effects are still unclear, estrogen seems to play a role in pain perception. Estrogen has dual effects, both pro- and anti-inflammatory. The increased pain sensation is thought to be mainly associated with sudden changes in estrogen levels during the menstrual cycle. That explains why many chronic pain symptoms of IBS are less severe or less common in pregnant women. In postmenopausal women, generally lower levels of estrogen also tend to alleviate IBS symptoms. (2.)

Androgens may alleviate pain

Increased levels of androgens, particularly testosterone seem to reduce pain in both men and women. These hormones (higher in men than women) tend to protect the body against the development of chronic pain. This is supported by the evidence that transsexual individuals that are treated with testosterone report improvement in chronic pain, especially headaches. (2.)

    Increase in hormone levels

    Women are more likely to seek medical care

    It, however, needs to be taken into consideration that in Western countries the expression of pain is more socially acceptable among women. This may explain why women are more likely to seek medical care to manage their IBS symptoms. Women also tend to be more concerned about social norm expectations such as the ability to take care of others, their body image affected by bloating, the lack of desire to engage in sex, etc. Men tend to ignore their symptoms, or they often downplay the significance of their issues. Seeking medical care to treat IBS symptoms should be normalized among both men and women to ensure every individual gets the right treatment,

    Summary

    There is some evidence showcasing that IBS symptoms are more common among women and/or the symptom presentation in women is more severe. It could be caused by several factors including fluctuating sex hormone levels during the menstrual cycle, endometriosis, or chronic exposure to stress. It should be of great importance to not only appreciate women on the 8th of March but also to ensure that the research into why certain diseases affect primarily women and how to prevent them continues growing.

     

    References

    1. Chiaffarino, F., Cipriani, S., Ricci, E., Mauri, P. A., Esposito, G., Barretta, M., Vercellini, P., & Parazzini, F. (2020). Endometriosis and irritable bowel syndrome: a systematic review and meta-analysis. Archives of Gynecology and Obstetrics303(1), 17–25. https://doi.org/10.1007/s00404-020-05797-8
    2. Mulak, A., & Taché, Y. (2010). Sex difference in irritable bowel syndrome: do gonadal hormones play a role? Gastroenterologia Polska: Organ Polskiego Towarzystwa Gastroenterologii17(2), 89–97. https://pubmed.ncbi.nlm.nih.gov/25435761/
    3. Pati, G. K., Kar, C., Narayan, J., Uthansingh, K., Behera, M., Sahu, M. K., Mishra, D., & Singh, A. (n.d.). Irritable Bowel Syndrome and the Menstrual Cycle. Cureus13(1). https://doi.org/10.7759/cureus.12692
    4. Narayanan, S. P., Anderson, B., & Bharucha, A. E. (2021). Sex- and Gender-Related Differences in Common Functional Gastroenterologic Disorders. Mayo Clinic Proceedings96(4), 1071–1089. https://doi.org/10.1016/j.mayocp.2020.10.004‌