Levonorgestrel Intrauterine System (LNG-IUS)
For heavy periods with a thick endometrial lining, use the levonorgestrel intrauterine system (LNG-IUS/Mirena) as your first-line contraceptive choice. This is the most effective medical treatment for reducing menstrual blood loss and will simultaneously thin your endometrial lining while providing contraception 1, 2, 3.
Why LNG-IUS is Superior
The LNG-IUS consistently outperforms all other medical options for heavy menstrual bleeding:
- Reduces menstrual blood loss by 80% at 4 months, 95% at 1 year, and achieves amenorrhea (no periods) in many women by 2 years 4
- More effective than combined oral contraceptives, oral progestogens, tranexamic acid, and NSAIDs for reducing bleeding 2, 3
- Directly thins the endometrial lining - studies show a mean reduction of 3.4 mm in endometrial thickness at 12 months 1
- Improves hemoglobin levels by an average of 1.06 g/dL at 12 months, correcting anemia from blood loss 1
Clinical Evidence Hierarchy
The 2010 European clinical practice guidelines explicitly rank treatment efficacy for abnormal uterine bleeding with levonorgestrel IUD as the #1 most effective option, followed by tranexamic acid, then oral contraceptives 3. A 2012 systematic review confirmed the LNG-IUS reduces menstrual blood loss to a greater extent than all other medical therapies 2.
When directly compared to combined oral contraceptives, the LNG-IUS was significantly more effective (OR 0.21,95% CI 0.09 to 0.48) 5.
What to Expect
Common side effects during the first 6 months:
- Intermenstrual spotting or irregular bleeding (most common initially)
- This typically resolves; by 3 months, 77.7% of women achieve cure of heavy bleeding 1
- 28% of women develop amenorrhea, which is a therapeutic benefit, not a problem 1
Contraindications to check before insertion:
- Active pelvic infection (purulent cervicitis, chlamydia, or gonorrhea) 6
- Pregnancy (perform pregnancy test if uncertain)
- Uterine cavity abnormalities that would prevent proper placement
Alternative Options (If LNG-IUS Cannot Be Used)
If the LNG-IUS is contraindicated or not tolerated:
Combined hormonal contraceptives (pills, patch, or vaginal ring) - moderately effective, reducing bleeding in 77% of women compared to 3% with placebo 5. These also thin the endometrium through regular hormonal cycling.
Tranexamic acid - second-line medical option, particularly if hormonal contraception is contraindicated or you desire immediate pregnancy 3
Critical Pitfall to Avoid
Before inserting any IUD or starting hormonal contraception, ensure you have appropriate evaluation of the thickened endometrium. While the LNG-IUS will treat the heavy bleeding and thin the lining, if you're premenopausal, transvaginal ultrasound is appropriate for initial assessment 7. The thickness alone doesn't indicate pathology in premenopausal women, but abnormal echogenicity or texture warrants endometrial sampling 7.
Do not delay IUD placement waiting for additional testing if basic evaluation is reassuring - the benefits of starting treatment outweigh risks in most clinical scenarios 6.