Why this topic matters: Dysmenorrhoea is menstrual pain caused by uterine contractions and prostaglandins. Primary dysmenorrhoea commonly begins in adolescence and improves within about 72 hours; secondary dysmenorrhoea results from conditions such as endometriosis, adenomyosis, fibroids, pelvic infection or an obstructive anomaly. Most episodes are managed with planned analgesia, but severe or atypical pain can signal ectopic pregnancy, ovarian torsion, pelvic infection, haemorrhage, appendicitis or another emergency. Students should relieve pain while investigating red flags and protecting dignity.
Learning objectives
- Define primary and secondary dysmenorrhoea and explain prostaglandin-mediated pain.
- Recognise typical symptoms, atypical features and emergency red flags.
- Take a menstrual, pregnancy, sexual-health, bowel/bladder and medication history sensitively.
- Provide safe analgesia, supportive care, assessment and referral for persistent or severe pain.
- Plan adolescent-friendly education, prevention of recurrence and endometriosis/pelvic disease follow-up.
Definition and physiology
Dysmenorrhoea means painful menstruation. In primary dysmenorrhoea, increased endometrial prostaglandins cause strong uterine contractions, temporary ischaemia and cramping without an identifiable pelvic disease. Pain usually starts shortly before or at the beginning of menstruation, may radiate to the back or thighs, and often improves over 1–3 days.
Secondary dysmenorrhoea is menstrual pain caused by pelvic pathology. Endometriosis is a common cause, but adenomyosis, fibroids, pelvic inflammatory disease, ovarian cysts, cervical stenosis, obstructive Müllerian anomalies and intrauterine devices may contribute. Progressive or treatment-resistant pain deserves investigation rather than repeated reassurance.
Primary versus secondary dysmenorrhoea
| Feature | Primary | Secondary |
|---|---|---|
| Onset | Often begins 6–12 months after menarche when ovulatory cycles develop. | May begin later, after years of painless periods, or progressively worsen. |
| Timing | Starts just before/at bleeding and lasts up to about 72 hours. | May start well before bleeding, persist after it or occur between periods. |
| Associated features | Nausea, diarrhoea, headache, fatigue, back/thigh pain. | Dyspareunia, infertility, heavy/irregular bleeding, discharge, bowel/bladder pain or abnormal examination. |
| Examination/tests | Usually normal; diagnosis is clinical when red flags are absent. | May show tenderness, mass or abnormal imaging; investigate the underlying cause. |
| Response | Often responds to NSAIDs and/or hormonal treatment. | Requires cause-directed treatment and gynaecology referral if persistent. |
Symptoms
- Cramping suprapubic pain, low-back ache or pain radiating to the inner thighs.
- Nausea, vomiting, diarrhoea, bloating, headache, dizziness, fatigue and faintness.
- Heavy bleeding, clots, school/work absence, sleep disruption and reduced activity.
- Severe pain with fever, discharge, dyspareunia, painful defecation, dysuria or infertility suggests secondary disease.
Emergency red flags: positive/possible pregnancy, sudden one-sided pain, syncope, shock, severe vomiting/dehydration, fever, guarding/rebound, heavy unexplained bleeding, new pelvic mass, acute urinary retention, blood in stool/urine or pain that is dramatically different from usual.
First contact and compassionate assessment
- Provide privacy and ask the patient to describe the pain in their own words. Do not dismiss severe menstrual pain as normal or exaggeration.
- Assess ABCDE and vital signs before routine analgesia questions; identify shock, infection, pregnancy and acute abdomen.
- Ask consent before sensitive sexual/reproductive questions or examination. Offer a chaperone and adolescent-friendly communication.
- Give appropriate analgesia early while continuing assessment; pain relief does not prevent diagnosis when the patient is reassessed.
- Explain the plan, likely causes, warning signs and follow-up. Use teach-back rather than assuming understanding.
ABCDE assessment
A — Airway
- Assess vomiting, consciousness and aspiration risk; support the airway if severe pain, opioid treatment or collapse occurs.
B — Breathing
- Measure rate and SpO₂; consider pulmonary embolism, anaemia, sepsis or anxiety when breathlessness is present.
C — Circulation
- Check pulse, BP, capillary refill, bleeding, hydration and temperature. Insert IV access if shock, severe vomiting or significant bleeding.
- Give isotonic fluid for dehydration under protocol and reassess after each bolus.
D — Disability
- Record AVPU/GCS and glucose when faint, confused, profoundly weak or medicated.
- Assess distress, anxiety, self-harm risk and impact on school/work without labelling symptoms as psychological.
E — Exposure
- Assess abdomen, pallor, fever, vaginal bleeding, discharge, scars and mass with consent and dignity.
Focused history
| Area | Questions | Purpose |
|---|---|---|
| Pain pattern | When did it begin? Before or after bleeding? How long, how severe, one/both sides, radiating, different from usual? | Distinguishes primary pattern from torsion, ectopic, endometriosis or acute abdomen. |
| Menstrual | Age at menarche, cycle, flow, clots, irregularity, last period and bleeding between periods. | Assesses primary/secondary causes, anaemia and pregnancy. |
| Pregnancy/sexual health | Pregnancy possibility, contraception, sexual activity, discharge, dyspareunia and STI risk. | Pregnancy and PID can be emergencies; ask privately and respectfully. |
| Bowel/bladder | Painful stool/urination, constipation/diarrhoea, rectal/urinary blood. | Suggests endometriosis, infection or urinary/GI pathology. |
| Treatment response | What was taken, dose/time, effect, allergies, ulcer/kidney disease, anticoagulants and hormonal medicines? | Prevents NSAID overdose and guides safe treatment. |
| Impact/safety | Missed school/work, sleep, mood, bullying, abuse or inability to access menstrual products? | Supports holistic care and safeguarding. |
Differential diagnosis when pain is severe
| Condition | Clues | Urgent action |
|---|---|---|
| Ectopic pregnancy | Pregnancy possibility, unilateral pain, bleeding, shoulder pain, syncope or shock. | Pregnancy test, IV access, resuscitation and emergency gynaecology. |
| Ovarian torsion/cyst rupture | Sudden unilateral pain with vomiting, mass or peritoneal signs. | Urgent ultrasound/gynaecology; do not delay for analgesia response. |
| PID/tubo-ovarian abscess | Fever, discharge, pelvic tenderness, dyspareunia or sepsis. | Pregnancy test, antibiotics and admission/referral if severe. |
| Endometriosis/adenomyosis | Progressive pain, dyspareunia, bowel/bladder symptoms, infertility or heavy bleeding. | Gynaecology assessment and ultrasound; ongoing management plan. |
| Appendicitis/urinary/GI disease | Focal right lower-quadrant pain, urinary symptoms, diarrhoea, obstruction or fever. | General surgical/renal assessment and targeted tests. |
Investigations
- Pregnancy test in every patient of reproductive potential with significant pelvic pain or bleeding.
- Full blood count for heavy bleeding/anaemia, urinalysis, STI testing when indicated, CRP and renal function before prolonged NSAIDs.
- Pelvic ultrasound for atypical, severe, persistent or secondary dysmenorrhoea; a normal scan does not exclude endometriosis.
- Further MRI, laparoscopy or specialist tests depend on suspected endometriosis, adenomyosis, fibroids, congenital obstruction or other pathology.
Acute treatment of primary dysmenorrhoea
- Offer a non-steroidal anti-inflammatory drug (NSAID) early—often at the start of pain or bleeding—if not pregnant and without renal disease, ulcer, significant asthma sensitivity, anticoagulation or allergy. Follow local product dosing.
- Paracetamol/acetaminophen may be used when NSAIDs are contraindicated or as advised; avoid duplicate combination products.
- Use heat to the lower abdomen/back, comfortable positioning, hydration, rest, gentle movement and antiemetics if needed.
- For severe refractory pain, use monitored titrated opioid only after dangerous causes are assessed; reassess sedation, respiratory rate and constipation.
- Give a written plan for the next cycle rather than waiting until pain is maximal, and arrange review if treatment fails.
Hormonal and cause-directed care
- Combined hormonal contraception, progestogen therapy or a hormonal intrauterine system may reduce ovulation, prostaglandin exposure and bleeding; discuss contraindications, pregnancy goals and adherence.
- Suspected endometriosis needs a planned gynaecology pathway; severe pain despite NSAIDs/hormones, bowel/bladder pain, infertility or abnormal examination warrants referral.
- Treat PID, fibroids, adenomyosis, anaemia, congenital obstruction and other causes according to specialist guidance.
- In adolescents, do not delay endometriosis evaluation when pain causes school absence or persists despite empiric treatment.
Nursing and EMT interventions
- Use a pain score, functional assessment and menstrual diary; reassess after medicine, heat and fluids.
- Monitor vital signs, bleeding, hydration, nausea, renal function and medicine adverse effects.
- Protect privacy; use respectful menstrual language and ask about access to pads, water, toilets and safe changing facilities.
- Teach safe NSAID timing, contraindications, maximum prescribed dose and signs of GI bleeding/allergy/renal injury.
- Provide school/work documentation when needed and arrange follow-up rather than repeated emergency-only visits.
Prevention and education
- Track two or more cycles: pain score, bleeding, bowel/bladder symptoms, medicines, missed activities and mood.
- Take prescribed NSAID early, maintain hydration, use heat and continue gentle activity when safe.
- Seek urgent care for collapse, positive pregnancy test, sudden one-sided pain, fever, heavy bleeding, persistent vomiting or pain unlike usual.
- Address anaemia, nutrition, menstrual hygiene and psychosocial distress; normalise help-seeking without normalising disabling pain.
- Review contraception and fertility goals during hormonal treatment and refer for persistent/secondary symptoms.
Clinical scenarios
Scenario 1 — Primary pattern: A 15-year-old has cramping beginning with each period, normal examination and no red flags. Provide privacy, validate the pain, offer an age-appropriate NSAID plan if safe, heat, school support and follow-up; reassess if pain persists despite treatment.
Scenario 2 — Secondary warning: A 23-year-old has progressively worsening pain, dyspareunia and painful defecation despite NSAIDs. Arrange pregnancy/STI assessment and gynaecology referral for possible endometriosis rather than repeatedly treating “normal cramps.”
Scenario 3 — Emergency mimic: A patient reports “period pain” but is pale, faint, vomiting and has unilateral abdominal tenderness. Perform ABCDE, pregnancy test, IV access, fluids/analgesia and urgent imaging/gynaecology review for ectopic pregnancy, torsion or haemorrhage.
Common errors to avoid
- Dismissing disabling menstrual pain as normal or assuming adolescents cannot have endometriosis.
- Failing to check pregnancy before treating severe pelvic pain.
- Giving NSAIDs despite pregnancy, renal disease, ulcer, anticoagulation or allergy, or combining multiple NSAIDs.
- Using opioids repeatedly without reassessment, respiratory monitoring and a diagnostic plan.
- Missing torsion, ectopic pregnancy, PID, appendicitis, urinary disease or severe anaemia.
PERIOD SAFE: P — Pregnancy test/red flags; E — Evaluate ABCDE; R — Record cycle/pain pattern; I — Investigate secondary causes; O — Offer early safe analgesia; D — Discuss hormonal options; S — School/work impact; A — Anaemia/STI screen; F — Follow-up; E — Escalate atypical pain.
Revision questions
- Define primary and secondary dysmenorrhoea.
- Explain the role of prostaglandins and why NSAIDs help.
- List six red flags requiring emergency assessment.
- Why is a pregnancy test important before treating severe pelvic pain?
- When should an adolescent with painful periods be referred for possible endometriosis?
- Outline safe patient education for NSAID use.
Key takeaways
Period pain deserves treatment and investigation when it is severe or atypical. Relieve pain early, check pregnancy and red flags, identify secondary causes, use medicines safely and arrange follow-up when symptoms impair life or fail to improve.
References for further study
- ACOG. Dysmenorrhea: Painful Periods.
- NICE Clinical Knowledge Summaries. Dysmenorrhoea: assessment and management.
- WHO. Menstrual health and menstrual pain resources.
- RCOG. Endometriosis and chronic pelvic pain patient information.
- Follow current Uganda Ministry of Health and local gynaecology protocols for analgesia, STI care, pregnancy assessment and referral.