Preparatory Mindset
Menstrual disorders are the most common reason women see a gynaecologist — and the chapter where HPO axis physiology (ch01) becomes clinical. The exam mindset: abnormal uterine bleeding (AUB) in a reproductive-age woman → pregnancy test FIRST; then sort by PALM-COEIN (structural vs non-structural). Amenorrhoea = pregnancy → hypothalamic/pituitary → ovarian → outflow; dysmenorrhoea = primary (prostaglandin-driven, NSAIDs work) vs secondary (endometriosis, adenomyosis); PCOS = oligo-anovulation + hyperandrogenism + polycystic ovaries (Rotterdam criteria). Menopause = FSH rise + amenorrhoea ≥12 months. The unifying tool: endometrial biopsy for any woman ≥45 (or <45 with risk factors) with AUB — rule out hyperplasia/cancer before treating symptoms.
Core Concepts
1. Abnormal uterine bleeding (AUB) — PALM-COEIN
| Category | Components |
|---|---|
| P — Polyp | Endometrial polyp (USS/hysteroscopy) |
| A — Adenomyosis | Endometrial glands in myometrium (bulky tender uterus, heavy pain) |
| L — Leiomyoma (fibroid) | Submucosal (heavy bleeding) / intramural / subserosal |
| M — Malignancy & hyperplasia | Endometrial hyperplasia/carcinoma (risk: age, obesity, unopposed estrogen, PCOS) |
| C — Coagulopathy | von Willebrand, platelet dysfunction (heavy bleeding since menarche) |
| O — Ovulatory dysfunction | Anovulatory (PCOS, perimenopause, thyroid, prolactin, stress) |
| E — Endometrial | Infection, IUD, atrophic |
| I — Iatrogenic | Hormonal contraception, anticoagulants, tamoxifen |
Key definitions:
- Menorrhagia: heavy regular bleeding >80 mL/cycle or duration >7 days.
- Metrorrhagia: irregular bleeding between periods.
- Postmenopausal bleeding: >12 months amenorrhoea + bleeding — endometrial cancer until proven otherwise → urgent USS + endometrial biopsy.
Workup: pregnancy test; FBC (anaemia); USS (endometrial thickness, fibroids, polyps, adnexal); endometrial biopsy (Pipelle/hysteroscopy) if ≥45, unopposed estrogen, PCOS, obesity, or failed medical therapy; coagulation screen if heavy since menarche; thyroid/prolactin if ovulatory dysfunction suspected.
Treatment ladder:
| Non-structural (O/E) | Structural (P/A/L) |
|---|---|
| Medical first: tranexamic acid, NSAIDs (mefenamic), levonorgestrel IUS (Mirena) — the most effective medical option, combined OCP, cyclical progesterone, danazol/GnRH-a (short-term) | Hysteroscopic polypectomy/myomectomy; endometrial ablation (no fertility desire); hysterectomy (failed conservative) |
| Correct the cause (PCOS, thyroid) | Malignancy/hyperplasia → staging + hysterectomy ± adjuvants |
2. Amenorrhoea
Definitions: primary = no menarche by 15 years (or by 3 years post-thelarche); secondary = no menses ≥3 months (or ≥6 months per older criteria) in a previously menstruating woman.
Step 1 — pregnancy test always. Then localise the lesion:
| Level | Causes | Key test |
|---|---|---|
| Uterine/outflow | Asherman (adhesions), imperforate hymen, Müllerian agenesis | USS, hysterosalpingogram |
| Ovarian | Premature ovarian insufficiency (FSH ↑, estrogen ↓), PCOS (anovulation) | FSH, LH, estradiol, AMH |
| Pituitary | Hyperprolactinaemia (prolactinoma), Sheehan (postpartum pituitary necrosis) | Prolactin, MRI if high |
| Hypothalamic | Functional (stress, weight loss, exercise — "athletic amenorrhoea"), Kallmann | LH/FSH low, estradiol low |
| Thyroid/adrenal | Hypo/hyperthyroidism, CAH | TSH, cortisol |
Treatment: per cause — PCOS (lifestyle + ovulation induction/OCP), prolactinoma (dopamine agonist), functional hypothalamic (nutrition/exercise correction, HRT for bone protection), outflow (surgical).
3. PCOS (Rotterdam 2003 criteria — 2 of 3)
- Oligo/anovulation (oligomenorrhoea/amenorrhoea)
- Clinical ± biochemical hyperandrogenism (hirsutism, acne; elevated testosterone)
- Polycystic ovaries on USS (≥12 follicles 2-9 mm per ovary or ovarian volume >10 mL)
Exclude other causes (CAH, Cushing, prolactinoma, thyroid).
Consequences: anovulatory infertility, endometrial hyperplasia/cancer risk (unopposed estrogen), metabolic syndrome/type 2 diabetes (insulin resistance), dyslipidaemia, obstructive sleep apnoea, depression.
Management:
- Lifestyle (weight loss 5-10%) — first-line; improves ovulation and metabolic profile.
- Cycle control: combined OCP (also treats acne/hirsutism), cyclical progestogens.
- Hirsutism: OCP, anti-androgens (spironolactone — not in pregnancy), cosmetic.
- Infertility: letrozole (first-line ovulation induction), clomiphene, metformin adjunct (esp. if glucose intolerance), then gonadotrophins/IVF.
- Long-term: screen glucose/lipids; annual endometrial protection (progestogen if amenorrhoeic).
4. Dysmenorrhoea
| Type | Features | Treatment |
|---|---|---|
| Primary | Starts within 3 years of menarche, crampy, day 1-2, normal pelvis | NSAIDs (prostaglandin inhibition), heat, exercise, OCP |
| Secondary | Older onset, worsening, associated with endometriosis, adenomyosis, fibroids, PID, IUCD | Treat cause; Mirena IUS, GnRH-a for endometriosis, surgery (excision, hysterectomy for adenomyosis) |
Endometriosis (ch12) — the most common secondary cause: painful periods, deep dyspareunia, chronic pelvic pain, subfertility — diagnosed by laparoscopy (gold standard).
5. Menopause and perimenopause
- MHT/HRT (estrogen ± progestogen) — most effective for vasomotor symptoms + bone protection; progestogen required if uterus present (endometrial protection); start within 10 years of menopause / age <60 for best benefit-risk; avoid in breast cancer, VTE history, undiagnosed bleeding. - Alternatives: SSRIs/SNRIs (paroxetine, venlafaxine) for vasomotor; vaginal estrogen for atrophy; non-hormonal bone therapy (bisphosphonates). - Lifestyle: calcium/vitamin D, weight-bearing exercise, smoking cessation.
- Definition: 12 months amenorrhoea, usually 45-55 years; FSH ↑, estradiol ↓.
- Symptoms: vasomotor (hot flushes, night sweats — from declining estrogen), sleep disturbance, mood change, vaginal dryness/atrophy, dyspareunia, urinary symptoms; long-term — osteoporosis, cardiovascular risk.
- Diagnosis: clinical (age + symptoms); FSH not routinely needed (except atypical age/amenorrhoea workup).
- Treatment:
High-Yield Points
| Topic | Must-remember |
|---|---|
| AUB first test | Pregnancy test (any reproductive-age woman) |
| PALM-COEIN | Structural (Polyp, Adenomyosis, Leiomyoma, Malignancy) vs non-structural (Coagulopathy, Ovulatory, Endometrial, Iatrogenic) |
| Endometrial biopsy | ≥45 years or risk factors with AUB |
| Postmenopausal bleeding | Endometrial cancer until proven otherwise |
| Most effective medical AUB | Levonorgestrel IUS (Mirena) |
| Amenorrhoea | Pregnancy → outflow → ovarian → pituitary → hypothalamic (FSH/LH/estradiol/prolactin localise) |
| PCOS criteria | 2 of 3: oligo-anovulation, hyperandrogenism, polycystic ovaries |
| PCOS first-line | Lifestyle (5-10% weight loss) |
| PCOS infertility | Letrozole first-line |
| PCOS risk | Endometrial cancer (unopposed estrogen) + T2DM |
| Primary dysmenorrhoea | NSAIDs (prostaglandins) |
| Menopause | 12 months amenorrhoea; HRT window <60 / <10 yr post-menopause |
Topic Summary
Menstrual disorders run from AUB (PALM-COEIN) — pregnancy test first, endometrial biopsy when indicated, Mirena IUS as the medical mainstay — through amenorrhoea (localise the HPO axis lesion), PCOS (Rotterdam 2-of-3; lifestyle + letrozole), dysmenorrhoea (primary → NSAIDs; secondary → find endometriosis), to menopause (12 months amenorrhoea; HRT in the right window). The underlying principle from ch01 returns: understand the hormonal cycle, and every menstrual disorder becomes a derangement of it.
LMCHK OSCE Practice — Heavy Periods in a 46-Year-Old
Station setup: A 46-year-old woman presents with 6 months of increasingly heavy, prolonged periods (soaking through pads, clots), causing fatigue. She has regular cycles, no pain. FBC: Hb 92 g/L, MCV 78. USS: endometrial thickness 9 mm (proliferative phase), small 2-cm submucosal fibroid. No hormone use.
Candidate tasks (8 min):
- Take a focused history (pregnancy? bleeding pattern, family history of endometrial/breast cancer, weight, PCOS).
- Explain the likely mechanism (submucosal fibroid + perimenopausal anovulation) contributing to menorrhagia and anaemia.
- Order appropriate tests: pregnancy test, FBC/ferritin, USS, and endometrial biopsy (≥45 with AUB — rule out hyperplasia/cancer).
- Discuss management options: medical (tranexamic acid, Mirena IUS, OCP) vs surgical (hysteroscopic myomectomy, endometrial ablation, hysterectomy) — factoring her age, bleeding severity, fertility wishes.
- Counsel on iron replacement for the anaemia and follow-up.
Key marking cues:
- Pregnancy test first.
- Orders endometrial biopsy (age ≥45 + AUB) — the safety essential.
- Recognises submucosal fibroid + anovulation as the structural/non-structural mix.
- Gives the treatment ladder (Mirena, tranexamic acid, surgical options).
- Addresses anaemia (iron) and follow-up.