Can Norethisterone (Primolut N) Be Used for Anovulatory Dysfunctional Uterine Bleeding in a 14-Year-Old?
Yes, norethisterone (Primolut N) can be used to stop prolonged vaginal bleeding due to anovulatory dysfunctional uterine bleeding in a 14-year-old girl, administered as oral progestin therapy for 10-14 days per month. 1, 2
Treatment Approach for Adolescent Anovulatory Bleeding
First-Line Medical Management
Oral progestins are the appropriate treatment for anovulatory dysfunctional uterine bleeding in adolescents, with norethisterone being an acceptable second-choice progestin option 3
The standard regimen is norethisterone 5-10 mg three times daily from day 12-25 of the cycle (or medroxyprogesterone acetate 10 mg daily for 10-14 days per month), which effectively reduces menstrual blood loss and controls bleeding patterns 1, 2
For adolescents specifically, medroxyprogesterone acetate administered orally once daily for 10 days each month for ≥3 months is the recommended approach, with close monitoring thereafter 2
Important Clinical Considerations
Micronized progesterone (MP) is the first-choice progestin when available due to lower cardiovascular and thrombotic risk, with norethisterone, medroxyprogesterone acetate (MPA), and dydrogesterone as second choices 3
Norethisterone requires a minimum dose of 1 mg daily for continuous regimens or higher doses (5-10 mg three times daily) for cyclical treatment of acute bleeding 3, 1
The treatment goal is to stop acute bleeding, prevent future episodes, and prevent long-term complications including endometrial hyperplasia from unopposed estrogen 4, 5
Acute vs. Chronic Management
For acute heavy bleeding episodes, high-dose estrogen therapy may be needed first, followed by progestin stabilization 2
For chronic anovulatory bleeding in adolescents, cyclical progestin therapy (10-14 days per month) is the foundation of treatment, avoiding continuous estrogen exposure that increases endometrial cancer risk 4, 5, 2
Common Pitfalls to Avoid
Never use estrogen therapy alone in anovulatory bleeding except for profuse bleeding unresponsive to progestin, as it increases the risk of endometrial hyperplasia and cancer from unopposed estrogen 5
Progestins with anti-androgenic effects should be avoided in patients with potential hypoandrogenism, though this is less relevant in adolescent anovulatory bleeding 3
Ensure pregnancy is ruled out before initiating any hormonal therapy in reproductive-age patients 6, 7
Alternative Options if Norethisterone Fails
Combined hormonal contraceptives (CHCs) are effective for ovulatory dysfunction bleeding and can be used if the patient also requires contraception 6, 2
NSAIDs can be added to reduce bleeding volume further when used with hormonal therapy 3, 6
If bleeding persists despite medical therapy, further investigation with imaging or hysteroscopy is indicated to rule out structural causes 6, 7