A 32-year-old woman presents with heavy menstrual bleeding for the past 6 months. Pelvic examination and transvaginal ultrasound are normal. Hemoglobin is 9.8 g/dL. She is not on any anticoagulants. What is the drug of choice for the first-line medical management of her abnormal uterine bleeding?

Explanation

## First-Line Medical Management of Heavy Menstrual Bleeding **Key Point:** Tranexamic acid is the first-line pharmacological agent for heavy menstrual bleeding (menorrhagia) in women without structural uterine pathology. ### Mechanism of Action Transexamic acid is a fibrinolysis inhibitor that stabilizes clot formation by blocking plasminogen activation. It reduces menstrual blood loss by 40–50% in most patients. ### Dosing & Administration - **Dose:** 1–1.5 g orally, three times daily - **Duration:** 3–5 days during menstruation - **Onset:** Effects visible within 2–3 cycles ### Efficacy & Safety Profile | Feature | Tranexamic Acid | Mefenamic Acid | LNG-IUS | Estrogens | |---------|-----------------|----------------|---------|----------| | **First-line status** | Yes | Second-line | Third-line (if contraception needed) | Rarely used | | **Reduction in blood loss** | 40–50% | 20–30% | 80–90% | Variable | | **Onset of action** | 2–3 cycles | 1–2 cycles | 3–6 months | Immediate | | **Contraception** | No | No | Yes | No | | **Side effects** | Rare; GI upset | GI upset, dyspepsia | Irregular bleeding initially | Thromboembolism risk | **High-Yield:** Tranexamic acid is preferred over NSAIDs (mefenamic acid) because it is more effective and has a better safety profile. It does not require daily use and is taken only during menstruation. ### Clinical Pearl Transexamic acid is particularly useful in: - Ovulatory menorrhagia (normal ovulation but heavy bleeding) - Coagulopathy-related heavy bleeding - Women who decline hormonal contraception - Patients awaiting definitive treatment (hysterectomy, ablation) ### Why Not Other Options? **Mefenamic Acid (NSAID):** - Second-line agent; reduces blood loss by only 20–30% - Requires daily use throughout the cycle - GI side effects limit compliance **Levonorgestrel Intrauterine System (LNG-IUS):** - Third-line; most effective (80–90% reduction) but requires insertion - Takes 3–6 months for full effect - Reserved for women who also need contraception - Not first-line for isolated menorrhagia **Conjugated Estrogens:** - Rarely used in modern practice - Risk of thromboembolism and cardiovascular events - Reserved for acute, severe bleeding or when other agents fail [cite:Jeffcoate's Principles of Gynaecology 8e Ch 15] [cite:FIGO Menorrhagia Guidelines 2018]