A 32-year-old married woman presents to the gynaecology clinic 5 days after unprotected intercourse during her fertile window. She is breastfeeding her 3-month-old infant and is concerned about the safety of emergency contraception while nursing. Her last menstrual period was 12 days ago, and she has a regular 30-day cycle. She denies any contraindications to hormonal therapy. What is the most appropriate emergency contraceptive option for this patient?

Explanation

## Emergency Contraception in Lactating Women: Copper IUD **Key Point:** Copper T 380A IUD is the safest and most effective emergency contraceptive for lactating women because it is a **non-hormonal, non-systemic method** with no transfer into breast milk and >99% efficacy. ### Clinical Context The patient is 5 days post-intercourse and breastfeeding. At 5 days, levonorgestrel efficacy has dropped significantly (30–40%), whereas copper IUD remains highly effective up to 5 days post-intercourse. More importantly, the non-hormonal nature of the copper IUD eliminates concerns about milk transfer and infant exposure. ### Why Copper IUD Is Optimal 1. **Efficacy:** >99% effective; works by: - Direct spermicidal effect of copper ions - Inflammatory response in endometrium - Altered tubal motility - Does NOT require ovulation inhibition (works throughout the cycle) 2. **Lactation Safety:** - **Non-hormonal** — no systemic absorption - **No transfer into breast milk** — copper IUD is a local contraceptive device - **Breastfeeding can continue uninterrupted** without any risk to infant - Lactational amenorrhea is preserved (if applicable) 3. **Additional Benefit:** Provides long-term contraception (10+ years), which is valuable for a woman who has just had a 3-month-old infant and may wish to space pregnancies. **High-Yield:** Copper IUD is the **only emergency contraceptive method that is completely safe in lactating women** without any need to interrupt breastfeeding or express-and-discard protocols. ### Comparison of Emergency Contraceptives in Lactation | Method | Efficacy | Lactation Safe? | Milk Transfer | Recommendation | |---|---|---|---|---| | **Copper IUD** | >99% | ✓ Yes | None | **First-line** | | **Levonorgestrel** | 60–95% (decreases with time) | Partial | Minimal; <1% of maternal dose | Use if IUD unavailable; express-discard 8 h (conservative) | | **Ulipristal acetate** | 65–95% | ✗ No | Unknown; not studied | **Contraindicated** in lactation | | **Yuzpe regimen** | 50–80% | ✗ No | Estrogen inhibits lactation | **Contraindicated** in lactation | **Clinical Pearl:** The **lactational amenorrhea method (LAM)** provides ~98% contraceptive efficacy in the first 6 months postpartum if the woman is exclusively breastfeeding and amenorrheic. However, this patient is already at risk (unprotected intercourse), so emergency contraception is warranted. --- ## Mechanism of Copper IUD as Emergency Contraceptive ```mermaid flowchart TD A[Copper IUD inserted within 5 days of intercourse]:::action --> B[Copper ions released into uterine cavity]:::outcome B --> C{Mechanism of action} C -->|Sperm| D[Direct spermicidal effect]:::outcome C -->|Endometrium| E[Inflammatory response; altered receptivity]:::outcome C -->|Fallopian tube| F[Altered tubal motility and transport]:::outcome D --> G[Prevents fertilization]:::outcome E --> G F --> G G --> H[Pregnancy prevention >99%]:::outcome I[No systemic absorption; no milk transfer]:::action --> J[Safe in lactation]:::outcome ``` --- **Mnemonic:** **"CU-SAFE-LACT"** — **Cu**pper IUD is **SAFE** in **LACT**ation (non-hormonal, no milk transfer, no breastfeeding interruption needed).