Dysmenorrhoea and heavy menstrual bleeding — formative SAQs

SAQ 1 — Primary vs secondary dysmenorrhoea and the management ladder (20 marks, ~15 minutes)

A 15-year-old presents with painful periods that began about a year after menarche. The pain is midline, cramping, starts just before menses, lasts two days, and recurs predictably. An ibuprofen trial helped partially. She is not sexually active. Her mother is concerned the pain "has been worse the last three cycles" and wonders whether it is "just normal period pain." [1]

Questions

1. Define dysmenorrhoea, classify this presentation as primary or secondary, and justify your classification from the history. State when primary dysmenorrhoea typically begins and why. (5 marks) [1]
2. Give the stepwise management ladder for dysmenorrhoea with agent, dose, route, timing and rationale, and cite the supporting evidence. (6 marks) [5] [6]
3. List the history features that would reweight the assessment toward secondary dysmenorrhoea, and name the leading secondary cause in the adolescent. (5 marks) [1]
4. Describe how you would frame the consultation, including the role of seeing the young person alone and integrating the menstrual cycle as a vital sign. (4 marks) [2]

Model answer (must-hit)

1. Dysmenorrhoea is cyclic pelvic pain with menstruation. This is primary dysmenorrhoea: the pain is midline, cramping, cyclic and predictable, began about a year after menarche, and has no red-flag features. Primary dysmenorrhoea begins only once ovulatory cycles establish, typically 6 to 12 months after menarche, because the secretory-phase progesterone of an ovulatory cycle primes the endometrium to synthesise prostaglandins and leukotrienes — the mediators of the pain. It does not start from the very first period. [1]
2. The ladder: first, an NSAID at the onset of menses — ibuprofen 400 to 600 mg or naproxen 250 to 500 mg, with food, for 2 to 3 days of bleeding — because NSAIDs block prostaglandin synthesis and are more effective than placebo (Marjoribanks 2010, Cochrane). Second, the combined oral contraceptive if the NSAID is inadequate or contraception is desired, assessed over three cycles at an adequate dose; the oral contraceptive pill improves dysmenorrhoea over placebo (Wong 2009, Cochrane). Third, review adherence and reconsider a secondary cause. Fourth, refer for pelvic ultrasound and gynaecology. [5] [6]
3. Features that point to secondary dysmenorrhoea: pain not relieved by NSAIDs and the combined oral contraceptive; non-cyclic pain; chronic pelvic pain between periods; dyspareunia; dyschezia; GI/GU symptoms; and activity- or school-limiting pain out of proportion to a normal period. The leading secondary cause in the adolescent is endometriosis, which carries a long diagnostic delay. An obstructive Müllerian anomaly, pelvic infection, and an intrauterine device are the other secondary causes. [1]
4. Frame confidentiality up front with its limits, and see the young person alone so the sexual and psychosocial history can be taken completely; the menstrual assessment sits inside the HEEADSSS framework. Treat the menstrual cycle as a vital sign — an irregular or absent cycle is a signal of an eating disorder, over-training, or thyroid disease, not a nuisance. The recent worsening is explored, but the baseline pattern fits primary dysmenorrhoea. [2]

SAQ 2 — Heavy menstrual bleeding from menarche and the bleeding-disease screen (20 marks, ~15 minutes)

A 13-year-old is brought by her mother with heavy periods since her first menstrual period at menarche eight months ago. She soaks a pad every 1 to 2 hours on heavy days, passes clots larger than a 50-cent coin, and has iron-deficiency anaemia (haemoglobin 95 g/L, ferritin 8 micrograms/L). She bruises easily and bleeds after dental work; her mother had a hysterectomy for menorrhagia. [4]

Questions

1. Define heavy menstrual bleeding and reproduce the FIGO classification of its causes, identifying which arm dominates in the adolescent and the most likely cause in this case. (5 marks) [3] [4]
2. State which investigation is specifically indicated by this presentation, what it includes, and the timing caveat for interpreting it. (5 marks) [4]
3. Outline the stepwise medical management ladder for heavy menstrual bleeding, citing the evidence for the levonorgestrel intrauterine system. (6 marks) [8]
4. Describe the immediate management of her iron-deficiency anaemia and the safety-netting and follow-up you would provide. (4 marks) [4]

Model answer (must-hit)

1. Heavy menstrual bleeding is menstrual loss the young person finds excessive or that interferes with quality of life. The FIGO PALM-COEIN system classifies causes into the structural PALM arm (Polyp, Adenomyosis, Leiomyoma, Malignancy) and the non-structural COEIN arm (Coagulopathy, Ovulatory dysfunction, Endometrial, Iatrogenic, Not otherwise classified). In the adolescent the COEIN arm dominates — anovulatory cycles and coagulopathy. In this case, the bleeding from menarche, the easy bruising and dental bleeding, and the family history point to coagulopathy, most likely von Willebrand disease. [3] [4]
2. A bleeding-disease screen is indicated: von Willebrand factor antigen and activity (ristocetin cofactor), factor VIII, with blood-group-aware interpretation (von Willebrand factor levels rise with blood group O and with oestrogen), and a platelet count and platelet function screen. The timing caveat: von Willebrand factor levels fall during acute bleeding and the menstrual state, so a level drawn during active heavy bleeding is interpreted in that context, and a borderline or low level is repeated when the young person is stable. Haematology is involved when a disorder is confirmed or the screen is equivocal. [4]
3. The ladder: first, an NSAID or tranexamic acid 1 g three times daily for 2 to 4 days of bleeding. Second, add or switch to the combined oral contraceptive or an oral progestogen. Third, the levonorgestrel intrauterine system, the most effective long-term option for heavy menstrual bleeding — the Cochrane review (Bofill Rodriguez 2020) identifies it as more effective than oral medical therapies — with a warning that irregular spotting is expected in the first 3 to 6 months. Fourth, for acute severe bleeding, a hormonal taper plus tranexamic acid, with referral to haematology and gynaecology. [8]
4. Iron-deficiency anaemia is treated at the first visit: oral iron repletion is first-line for the stable adolescent; this young person's symptomatic anaemia warrants referral for consideration of intravenous iron. The safety-net is explicit — return if the bleeding increases, or if there is dizziness or presyncope. Follow-up at three cycles confirms response to the medical therapy and integrates haematology once the bleeding-disease screen returns. [4]