Dysmenorrhea for ABIM

Dysmenorrhea for the American Board of Internal Medicine Exam

Definition and Classification

Dysmenorrhea refers to painful menstrual cramps that occur with menstruation, typically causing cramping in the lower abdomen and pelvis.
It is classified into two main types:
Primary Dysmenorrhea: Menstrual pain without identifiable pelvic pathology, common in adolescence and young adulthood.
Secondary Dysmenorrhea: Menstrual pain associated with underlying pelvic pathology, more likely in older reproductive-age women.

Dysmenorrhea is one of the most common gynecologic complaints, affecting approximately 50-90% of reproductive-age women.
Primary dysmenorrhea usually begins within the first few years after menarche and tends to improve with age or after childbirth.

Pathophysiology

Caused by increased production of prostaglandins (particularly PGF2α) in the endometrium during menstruation.
Prostaglandins promote uterine contractions, reducing blood flow, leading to ischemia and pain.
High levels of leukotrienes and vasopressin also contribute to uterine hypercontractility and pain.

Due to identifiable pelvic pathology, such as:
Endometriosis: Endometrial tissue outside the uterus responds to hormonal changes, causing pain.
Adenomyosis: Endometrial tissue within the myometrium leads to an enlarged, tender uterus.
Leiomyomas (Fibroids): Uterine fibroids may distort the uterine cavity or cause localized pain.
Pelvic Inflammatory Disease (PID): Infection leading to inflammation and pain.
Intrauterine Devices (IUDs): Copper IUDs may be associated with increased menstrual pain.

Clinical Manifestations

Cramping pain in the lower abdomen and pelvis, often radiating to the back or thighs.
Pain typically starts 1-2 days before or at the onset of menstruation and peaks within the first 1-3 days of bleeding.
Accompanied by nausea, vomiting, fatigue, headache, and sometimes diarrhea.

Menstrual pain that may start earlier in the menstrual cycle and last longer than primary dysmenorrhea.
Pain may not correlate directly with menstruation and often includes dyspareunia (painful intercourse), abnormal uterine bleeding, or infertility.
Physical findings may reveal a tender or enlarged uterus (adenomyosis), adnexal masses (endometriosis or fibroids), or cervical motion tenderness (PID).

Diagnosis

Comprehensive menstrual and gynecologic history is essential, including timing, duration, and characteristics of pain, as well as associated symptoms like nausea or dyspareunia.
Physical examination can help identify signs of underlying pathology (e.g., adnexal masses, cervical motion tenderness, or uterine tenderness).

Generally not required for primary dysmenorrhea.
In secondary dysmenorrhea, consider testing if infection (PID) is suspected: CBC, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and cervical cultures for gonorrhea and chlamydia.

Transvaginal Ultrasound (TVUS): First-line imaging for secondary dysmenorrhea to evaluate for pelvic pathology such as fibroids, adenomyosis, or ovarian masses.
MRI: Used if TVUS findings are inconclusive or to evaluate for adenomyosis and deep infiltrating endometriosis.

Considered the gold standard for diagnosing endometriosis in secondary dysmenorrhea when other evaluations are inconclusive.
Allows direct visualization and biopsy of pelvic lesions.

Management

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs):
First-line treatment, as they inhibit prostaglandin synthesis, reducing uterine contractions and pain.
Examples: ibuprofen, naproxen, started 1-2 days before expected onset of menses and continued during menstruation.
Hormonal Contraceptives:
Combined oral contraceptives (COCs), hormonal IUDs (e.g., levonorgestrel IUD), and progestin-only methods reduce endometrial proliferation, lowering prostaglandin production.
Continuous hormonal contraceptive regimens may help in severe cases.
Alternative Therapies:
Heat therapy (heating pads), physical exercise, and dietary supplements (e.g., omega-3 fatty acids, magnesium) may provide relief.
Acupuncture and transcutaneous electrical nerve stimulation (TENS) have shown benefits in some patients.

Management depends on the underlying cause:
Endometriosis: First-line therapies include NSAIDs and hormonal treatments (COCs, GnRH agonists, or progestins).
Adenomyosis: Hormonal treatments, particularly the levonorgestrel IUD or GnRH agonists, can help reduce symptoms. Hysterectomy is a definitive option in severe, refractory cases.
Fibroids: Medical management includes hormonal therapy or GnRH agonists. Surgical options (myomectomy, hysterectomy, or uterine artery embolization) may be indicated in symptomatic cases.
Pelvic Inflammatory Disease: Antibiotic therapy is essential; NSAIDs may be used for pain relief.
IUD-Associated Pain: NSAIDs can manage pain related to copper IUDs. In persistent cases, IUD removal may be considered.

Complications

Although generally not associated with long-term complications, chronic pain may impact quality of life, causing missed work or school and limiting daily activities.

The complications depend on the underlying cause:
Endometriosis: Infertility, chronic pelvic pain, and adhesions.
Adenomyosis: Heavy menstrual bleeding, anemia, and uterine enlargement.
Fibroids: Heavy bleeding, anemia, infertility, and mass effect on surrounding organs.
Pelvic Inflammatory Disease: Chronic pelvic pain, infertility, and tubo-ovarian abscess formation.

Key Points

Dysmenorrhea is classified as primary (without pelvic pathology) or secondary (with identifiable pathology such as endometriosis or fibroids).
Primary Dysmenorrhea:

Common in young women, due to increased prostaglandin levels causing painful uterine contractions.
Managed with NSAIDs, hormonal contraceptives, and supportive therapies like heat application.

Often due to conditions like endometriosis, adenomyosis, fibroids, or pelvic inflammatory disease.
Symptoms may vary based on the underlying condition and may include dyspareunia, abnormal bleeding, and infertility.
Diagnosis may require imaging (TVUS, MRI) or laparoscopy for direct visualization.

Primary dysmenorrhea is treated with NSAIDs and hormonal therapy.
Treatment of secondary dysmenorrhea depends on the cause, with options ranging from hormonal therapy and pain management to surgical intervention.

Primary dysmenorrhea impacts quality of life but has no long-term sequelae.
Secondary dysmenorrhea may result in complications like infertility and chronic pain, depending on the underlying pathology.