What is the best treatment approach for a woman with adenomyosis, an enlarged uterus equivalent to an 18-week pregnancy, who is experiencing heavy menstrual bleeding and pain, and wants to preserve fertility?

Management of Adenomyosis with 18-Week Uterine Size and Fertility Preservation

For a woman with adenomyosis, an 18-week-sized uterus, and desire for fertility preservation, first-line treatment is a levonorgestrel-releasing intrauterine device (LNG-IUD 20 μg/day), which reduces menstrual blood loss by 71-95% and provides significant improvement in pain and bleeding, though it does not cure the disease. 1, 2, 3

Initial Medical Management Algorithm

Start with LNG-IUD as first-line therapy:

• The LNG-IUD acts primarily at the endometrial level with minimal systemic absorption, providing long-term symptom control while preserving the uterus and fertility potential 2, 3
• Follow-up at 3 months to assess symptom improvement 2, 3
• This approach is preferred over combined oral contraceptives, which are less effective than LNG-IUD for adenomyosis 1, 2

If LNG-IUD fails or is not tolerated, consider second-line hormonal options:

• GnRH antagonists are highly effective for heavy menstrual bleeding even with concomitant adenomyosis, though limited by hypoestrogenic effects 1, 2, 3
• Combination treatment with low-dose estrogen and progestin mitigates side effects including hot flushes, headaches, and bone mineral density loss 1
• GnRH agonists require add-back therapy with long-term use to prevent bone mineral loss 1, 2, 3
• High-dose progestins (medroxyprogesterone acetate 400-600 mg/day or megestrol acetate 160-320 mg/day) are effective alternatives 2

Surgical Considerations for Fertility Preservation

Conservative surgery (adenomyomectomy) should be considered only after medical management fails:

• Excision of adenomyosis is effective for symptom control (menorrhagia and dysmenorrhea) and possibly for adenomyosis-related infertility, with over three-fourths of women experiencing symptom relief 4
• Pregnancy rates after conservative surgical treatment show that three-fourths of patients conceived after surgery with or without adjuvant medical treatment 4
• Critical caveat: Surgical recurrence is common, with up to 44% of women experiencing symptom recurrence within one year after conservative surgery 1, 2
• These procedures require highly experienced surgeons and pose considerable risk of uterine rupture during subsequent pregnancies 5

Post-surgical adjuvant therapy:

• Early combined GnRH agonist therapy immediately following cytoreductive surgery with a delay of 4-6 months before attempting pregnancy is advisable, as adenomyosis tends to recur rapidly and the myometrium can be significantly disrupted during surgery 6

Alternative Interventional Option

Uterine artery embolization (UAE) for refractory cases:

• UAE provides 94% short-term and 85% long-term symptom improvement, with only 7-18% of patients requiring hysterectomy for persistent symptoms 1, 2
• Important limitation: Comprehensive data on fertility and pregnancy outcomes after UAE is lacking; patients must be counseled accordingly 2, 3
• UAE may be less effective when adenomyosis is the predominant condition compared to when fibroids predominate 2

Critical Pitfalls to Avoid

Understanding the limitations of medical therapy:

• No medical therapy eradicates adenomyosis lesions—all provide only temporary symptom relief with rapid recurrence after discontinuation 1, 2, 3
• Medical treatment does not affect future fertility in women with adenomyosis 2
• Assuming medical therapy will cure adenomyosis is incorrect; it only temporizes symptoms 1

Inappropriate surgical approaches:

• Myomectomy alone does not address adenomyosis and is ineffective for this condition 1
• Endometrial ablation has high failure rates in the presence of adenomyosis 1

Essential pre-treatment evaluation:

• Ensure endometrial biopsy has been performed to rule out endometrial cancer or hyperplasia, especially given the enlarged uterus size 1
• MRI should be performed to better characterize the extent of adenomyosis and exclude other pathologies 2

When to Consider Definitive Surgery

Hysterectomy remains the definitive treatment but should be reserved for:

• Failure of medical and interventional therapies 3
• Completion of childbearing 2
• Patient satisfaction rates up to 90% with definitive resolution 3
• When performed, the least invasive approach (vaginal or laparoscopic) should be chosen over abdominal hysterectomy 1, 2, 3