The simple idea (no memorising)
- Primary dysmenorrhoea — the pelvis is anatomically normal. The pain comes from prostaglandins (that same PGF₂α) making the womb muscle cramp hard. It usually starts in the teens/early twenties, soon after cycles become ovulatory.
- Secondary dysmenorrhoea — the pain is a symptom of a disease in the pelvis. It tends to appear later, in someone whose periods were previously fine.
| Feature | Primary | Secondary |
|---|---|---|
| Underlying pelvic disease | none | present |
| Typical age | younger (teens/20s) | later / reproductive age |
| Cause of pain | prostaglandins | an underlying condition |
| Examples | — | endometriosis, adenomyosis, fibroids, PID |
The mental shortcut
What helps
For primary pain, medicines that lower prostaglandins ease cramps, and hormonal methods that suppress ovulation (like the combined pill) calm the whole cycle. For secondary pain, the real fix is treating the underlying cause — which is why finding it matters.
Why it matters
"Painful periods" is one of the commonest reasons a woman sees a doctor. The whole clinical skill is deciding: is this a normal‑but‑crampy uterus, or is pain a messenger pointing at endometriosis, fibroids or infection? Those diseases are exactly where Part 3 is heading.
Quick check ✅
- In primary dysmenorrhoea, what causes the pain — and what does the pelvis look like?
- Name two conditions that cause secondary dysmenorrhoea.
Remember this 🌟
Where we're going next → Those "diseases to find" begin with a hormone imbalance you can often see — extra hair. Concept 16.