What is the cause of severe pelvic pain during menstruation (dysmenorrhea)?

From the Guidelines

Severe pelvic pain during menstruation, also known as dysmenorrhea, is most commonly caused by endometriosis, a condition where tissue similar to the lining of the uterus grows outside the uterus, leading to inflammation, scarring, and adhesions. The pain associated with endometriosis has little relationship to the type of lesions seen by laparoscopy, but it has been shown that the depth of endometriosis lesions correlates with the severity of pain 1.

Causes of Dysmenorrhea

• Endometriosis: a condition where tissue similar to the lining of the uterus grows outside the uterus, leading to inflammation, scarring, and adhesions
• Uterine contractions: caused by prostaglandins, which are hormone-like substances that cause the uterus to contract, leading to pain
• Other conditions: such as fibroids, adenomyosis, and pelvic inflammatory disease

Diagnosis and Treatment

Diagnosis of endometriosis is typically done through a combination of physical exam, medical history, and imaging tests such as ultrasound or MRI. Laparoscopy, a surgical procedure that allows a doctor to look inside the pelvis, is also used to confirm the diagnosis. Treatment options for dysmenorrhea include:

• Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or naproxen, which can help reduce pain and inflammation
• Hormonal birth control pills, which can help reduce menstrual pain by thinning the uterine lining and reducing prostaglandin production
• Other prescription medications, such as gonadotropin-releasing hormone (GnRH) agonists, which can help reduce the size of endometriosis lesions and relieve pain
• Surgery, such as laparoscopy or hysterectomy, which may be necessary in severe cases of endometriosis or other conditions causing dysmenorrhea

Lifestyle Modifications

In addition to medical treatment, lifestyle modifications can also help alleviate dysmenorrhea symptoms, such as:

• Applying heat to the lower abdomen using a heating pad or warm bath
• Engaging in regular physical activity, such as walking or swimming
• Practicing stress reduction techniques, such as deep breathing, meditation, or yoga
• Making dietary changes, such as reducing caffeine, salt, and alcohol intake, and increasing water consumption

It's essential to consult a healthcare provider to determine the underlying cause of dysmenorrhea and develop an effective treatment plan, as some conditions, such as endometriosis or fibroids, may require more aggressive treatment 1.

From the FDA Drug Label

In patients with primary dysmenorrhea, ibuprofen tablets have been shown to reduce elevated levels of prostaglandin activity in the menstrual fluid and to reduce resting and active intrauterine pressure, as well as the frequency of uterine contractions. The probable mechanism of action is to inhibit prostaglandin synthesis rather than simply to provide analgesia The cause of severe pelvic pain during menstruation (dysmenorrhea) is related to prostaglandin activity and uterine contractions.

• Prostaglandin synthesis is a key factor in the development of dysmenorrhea.
• Uterine contractions also play a role in the severity of the pain. 2

From the Research

Causes of Severe Pelvic Pain during Menstruation

• Severe pelvic pain during menstruation, also known as dysmenorrhea, is caused by the production of prostaglandins, which lead to uterine contractions and pain 3, 4, 5
• The cyclooxygenase pathway plays a key role in the production of prostaglandins, and increased levels of these compounds can cause uterine contractions, restrict blood flow, and stimulate pain receptors 4, 5
• Other factors that may contribute to dysmenorrhea include uterine hypercontractility, reduced uterine blood flow, and increased peripheral nerve hypersensitivity 4

Pathophysiology of Dysmenorrhea

• The pathophysiology of primary dysmenorrhea is complex and involves the interplay of various factors, including hormonal changes, uterine contractions, and pain perception 4, 5
• The production of prostanoids, particularly prostaglandins, is thought to play a key role in the development of dysmenorrhea 4, 5
• Uterine contractions, which are induced by prostaglandins, can lead to reduced uterine blood flow and the production of anaerobic metabolites, which stimulate pain receptors 5

Diagnosis and Treatment of Dysmenorrhea

• Diagnosis of primary dysmenorrhea is typically based on a patient's medical history and physical examination, and empiric treatment can be initiated without additional testing 5
• Effective treatments for dysmenorrhea include nonsteroidal anti-inflammatory drugs (NSAIDs) and contraceptive hormonal therapy, which can help reduce prostaglandin production and alleviate symptoms 3, 6, 4, 7, 5
• Other treatments, such as cyclooxygenase inhibitors, may also be effective in reducing symptoms of dysmenorrhea 4, 7