Progestin-Only Contraceptive for Adenomyosis
The levonorgestrel-releasing intrauterine device (LNG-IUD, 52 mg) is the first-line progestin-only contraceptive for adenomyosis, providing 71-95% reduction in menstrual blood loss with efficacy comparable to endometrial ablation. 1, 2
First-Line Recommendation: LNG-IUD
The LNG-IUD acts primarily at the endometrial level with minimal systemic progesterone absorption, making it ideal for managing both heavy menstrual bleeding and pain in adenomyosis 1, 2. This local mechanism of action is particularly advantageous as it minimizes systemic hormonal effects while maximizing therapeutic benefit at the site of pathology.
Key advantages of LNG-IUD:
- Reduces menstrual blood loss by 71-95% 1, 2
- Provides effective pain relief for dysmenorrhea and dyspareunia 3, 4
- Maintains long-term efficacy over 3+ years 3
- Only 15% discontinuation rate due to side effects 3
- Provides reliable contraception while treating symptoms 5, 2
Alternative Progestin-Only Options
When LNG-IUD is not suitable or tolerated, consider these progestin-only alternatives in order of preference:
Dienogest 2 mg Daily
- Significantly reduces dysmenorrhea, dyspareunia, and heavy menstrual bleeding 3
- Maintains efficacy over 3 years in most patients 3
- Important caveat: 49% of patients required treatment switch after the first year due to side effects or need for contraception 3
- Recent RCT showed comparable pain reduction to LNG-IUD (VAS score reduction from 6.41 to 3.12) 4
- May provide superior quality of life improvement compared to LNG-IUD 4
Drospirenone 4 mg Daily
- Effectively improves heavy menstrual bleeding and dysmenorrhea 3
- Better long-term continuation rates than desogestrel 3
- Provides reliable contraception 3
Desogestrel 75 mcg Daily
- Improves heavy menstrual bleeding and dysmenorrhea 3
- Major limitation: Higher discontinuation rate due to reduced long-term efficacy 3
- Should be considered third-line among oral progestin-only pills 3
Clinical Algorithm for Selection
Step 1: Offer LNG-IUD as first-line unless contraindicated (uterine cavity distortion, active pelvic infection, or patient preference against intrauterine device) 1, 2
Step 2: If LNG-IUD declined or not tolerated, prescribe dienogest 2 mg daily as the preferred oral progestin-only option 3, 4
Step 3: If dienogest causes intolerable side effects or inadequate response, switch to drospirenone 4 mg daily 3
Step 4: Consider norethisterone acetate as second-line treatment in cases of intolerance or inadequate response to other progestins 3
Step 5: Reassess at 3 months to evaluate symptom improvement and side effect profile 2
Important Clinical Considerations
Monitoring parameters:
- Assess pain reduction using Visual Analog Scale at 3-month follow-up 3, 4
- Evaluate menstrual blood loss changes using validated tools 3, 4
- Screen for common side effects: irregular bleeding, breast tenderness, mood changes 3
Critical pitfall to avoid: Do not assume all progestin-only options are equivalent. The LNG-IUD has superior efficacy data specifically for adenomyosis compared to oral progestin-only pills, with the highest reduction in menstrual blood loss and lowest discontinuation rates 1, 2, 3.
Flexibility in management: The ability to switch between different progestins or routes of administration (intrauterine versus oral) helps optimize long-term outcomes when initial therapy is inadequate 3. This is particularly important given that adenomyosis requires long-term management and no medical therapy eradicates the disease—all provide only symptom control 6, 7.
Contraception benefit: All these progestin-only options provide contraception, which is advantageous for women not desiring pregnancy while managing adenomyosis symptoms 5, 2, 3.