Period Pain (Dysmenorrhea)

Introduction

Dysmenorrhea is the medical term for painful menstruation. It is one of the most common gynecological complaints, affecting up to 60–90% of women of reproductive age, with around 10–15% experiencing severe pain that interferes with daily activities.

Dysmenorrhea can be classified into:

Primary dysmenorrhea: painful periods in the absence of pelvic pathology, usually starting within 6–12 months of menarche.
Secondary dysmenorrhea: painful periods due to an underlying gynecological condition (e.g., endometriosis, adenomyosis, fibroids).

The pain typically presents as crampy, lower abdominal pain that radiates to the lower back or thighs. It is often accompanied by systemic symptoms such as nausea, vomiting, diarrhea, or headache.

Causes of Period Pain

1. Primary Dysmenorrhea

Caused by excessive production of prostaglandins (PGF2α, PGE2) in the endometrium during menstruation.
Leads to increased uterine contractility, ischemia, and pain.
Risk factors: early menarche, heavy menstrual flow, family history, smoking, stress.

2. Secondary Dysmenorrhea

Endometriosis: ectopic endometrial tissue outside uterus causes cyclic pain.
Adenomyosis: endometrial glands within myometrium.
Uterine fibroids: submucosal fibroids increase pain and bleeding.
Pelvic inflammatory disease (PID): chronic infection and adhesions.
Intrauterine device (IUD): copper IUDs may exacerbate pain.
Congenital uterine anomalies: obstructive Müllerian anomalies cause pain due to trapped menstrual blood.

Pathophysiology

In the luteal phase, progesterone primes the endometrium.
At menstruation, progesterone withdrawal leads to release of arachidonic acid, producing prostaglandins.
Excess prostaglandins cause:
- Strong uterine contractions.
- Vasoconstriction and reduced blood flow.
- Ischemic pain and increased nerve sensitivity.
In secondary causes, pathology adds to prostaglandin-mediated pain (e.g., inflammation in endometriosis).

Clinical Presentation

Pain pattern: crampy lower abdominal pain, starting 1–2 days before menstruation, peaking in first 24 hours, improving after 2–3 days.
Radiation: to lower back, thighs, groin.
Associated symptoms:
- Nausea, vomiting.
- Diarrhea, bloating.
- Fatigue.
- Headache, dizziness.
In secondary dysmenorrhea: pain may be progressive, occur outside menstruation, or be associated with infertility, dyspareunia, or abnormal bleeding.

Diagnosis

1. Clinical Assessment

History: onset (adolescence vs later life), severity, cycle regularity, impact on life.
Family history: dysmenorrhea, endometriosis.
Response to treatment: improvement with NSAIDs suggests primary dysmenorrhea.

2. Examination

Usually normal in primary dysmenorrhea.
Findings in secondary causes:
- Enlarged tender uterus (adenomyosis, fibroids).
- Nodularity in posterior fornix (endometriosis).
- Cervical motion tenderness (PID).

3. Investigations

Pelvic ultrasound: rule out structural abnormalities.
MRI: for adenomyosis or complex anomalies.
Laparoscopy: gold standard for diagnosing endometriosis.
STI screening: if PID suspected.

Management of Period Pain

Treatment depends on whether it is primary or secondary dysmenorrhea. The main goals are to relieve pain, improve quality of life, and treat underlying pathology if present.

1. General and Lifestyle Measures

Heat therapy: heating pads reduce uterine muscle spasm.
Exercise: aerobic exercise improves pelvic blood flow.
Dietary changes: omega-3 fatty acids, low-fat diet may reduce prostaglandin levels.
Stress management: yoga, meditation.

2. Pharmacological Treatment

a) Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

First-line therapy for primary dysmenorrhea. They inhibit cyclooxygenase (COX), reducing prostaglandin synthesis.

Ibuprofen: 400 mg orally every 6–8 hours, start 1–2 days before menstruation.
Naproxen sodium: 500 mg orally initially, then 250 mg every 6–8 hours.
Mefenamic acid: 500 mg orally every 8 hours during menstruation.
Diclofenac sodium: 50 mg orally every 8 hours, or 100 mg rectal suppository at onset of pain.

b) Hormonal Therapy

Suppresses ovulation and endometrial growth, reducing prostaglandin production.

Combined oral contraceptives (COCs): regulate cycles and decrease pain.
- Example: Ethinylestradiol 30 µg + levonorgestrel 150 µg orally once daily for 21 days, then 7-day break.
Progestin-only therapy:
- Medroxyprogesterone acetate: 10 mg orally daily for 10–14 days per cycle.
- Dienogest: 2 mg orally daily (effective in endometriosis-related pain).
- Levonorgestrel intrauterine system (LNG-IUS): 20 µg/day release, effective up to 5 years.

c) GnRH Agonists (for severe secondary dysmenorrhea, e.g., endometriosis)

Suppress ovarian estrogen production, inducing temporary hypoestrogenic state.

Leuprolide acetate: 3.75 mg intramuscular monthly.

d) Other Medications

Tranexamic acid (if heavy bleeding coexists): 1 g orally 3–4 times daily during menstruation.
Acetaminophen (paracetamol): mild cases, 500–1000 mg orally every 6 hours (less effective than NSAIDs).

3. Surgical and Interventional Treatment

Indicated for secondary dysmenorrhea or refractory cases.

Laparoscopic excision/ablation of endometriosis.
Myomectomy: for fibroids causing pain.
Hysterectomy: definitive treatment for severe refractory dysmenorrhea in women not desiring fertility.
Uterine nerve ablation (rare, not widely practiced).

Pharmacological Summary (Generic Names and Doses)

Ibuprofen: 400 mg orally every 6–8 hours.
Naproxen sodium: 500 mg initially, then 250 mg every 6–8 hours.
Mefenamic acid: 500 mg every 8 hours.
Diclofenac sodium: 50 mg every 8 hours orally, or 100 mg rectally at onset.
Ethinylestradiol + levonorgestrel: 30 µg/150 µg daily for 21 days + 7-day break.
Medroxyprogesterone acetate: 10 mg orally daily for 10–14 days/cycle.
Dienogest: 2 mg orally daily.
Levonorgestrel IUS: 20 µg/day release, effective for 5 years.
Leuprolide acetate: 3.75 mg IM monthly.
Tranexamic acid: 1 g orally 3–4 times/day during menstruation.
Acetaminophen (paracetamol): 500–1000 mg every 6 hours as needed.

Complications

Reduced quality of life: absenteeism from school or work.
Infertility: in secondary dysmenorrhea (e.g., endometriosis, fibroids).
Chronic pelvic pain: may persist even outside menstruation.
Anemia: if associated with heavy bleeding.
Psychological effects: depression, anxiety.

Prognosis

Primary dysmenorrhea: usually improves with age and after childbirth.
Secondary dysmenorrhea: prognosis depends on cause (endometriosis, fibroids may require long-term management).
Effective pain control is achievable in most cases with NSAIDs or hormonal therapy.

Preventive and Supportive Measures

Regular physical activity.
Maintaining healthy weight.
Avoid smoking (linked to more severe dysmenorrhea).
Early evaluation of worsening or atypical pain.
Use of menstrual tracking apps for cycle monitoring.

Saidala 24

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Monday, August 18, 2025

Period pain