What is the first‑line therapy for anovulatory dysfunctional uterine bleeding in a reproductive‑age woman who wishes to avoid pregnancy?

First-Line Treatment for Anovulatory Dysfunctional Uterine Bleeding

For a reproductive-age woman with anovulatory dysfunctional uterine bleeding who wishes to avoid pregnancy, combined oral contraceptives (COCs) containing 30-35 μg ethinyl estradiol are the first-line therapy, providing both menstrual regulation and effective contraception. 1, 2

Primary Treatment Approach

Combined Oral Contraceptives (Preferred)

• Monophasic COCs with 30-35 μg ethinyl estradiol plus a progestin (levonorgestrel or norgestimate) are the initial treatment of choice for anovulatory bleeding in women requiring contraception 2
• COCs decrease menstrual blood loss and cramping by inducing regular shedding of a thinner endometrium 2
• They provide additional benefits including improvement in acne and reduced risk of endometrial and ovarian cancers 2
• COCs can be combined with NSAIDs for additional reduction in blood loss if needed 1, 3

Alternative First-Line Options

Levonorgestrel-Releasing IUD (LNG-IUD)

• The LNG-IUD reduces menstrual blood loss by 71-95% and is the most effective medical option available 3, 4
• It should be strongly considered as first-line therapy, particularly in women with cardiovascular disease or those on anticoagulation, due to minimal systemic hormone exposure 3, 4
• Efficacy is comparable to endometrial ablation 3

Oral Progestins

• Medroxyprogesterone acetate 10 mg daily for 10 days each month can regulate cycles in anovulatory bleeding 5, 6
• Oral progestins taken for 21 days per month decrease menstrual blood loss and are suitable for cyclic heavy bleeding 3
• However, progestins reduce blood loss by only 20% in ovulatory women, making them less effective than LNG-IUD 4

Important Clinical Considerations

Contraindications to Estrogen Therapy

• Estrogen therapy is contraindicated in anovulatory bleeding except for profuse bleeding unresponsive to progestin, as it increases the risk of endometrial hyperplasia and cancer 4, 7
• Injectable depot medroxyprogesterone acetate (DMPA) is not recommended for dysfunctional uterine bleeding due to its prolonged action and difficulty predicting withdrawal bleeding 8

Cardiovascular Disease Patients

• Avoid NSAIDs and tranexamic acid in patients with cardiovascular disease or history of spontaneous coronary artery dissection due to increased thrombotic risk 3
• The LNG-IUD is preferred in these patients because of minimal systemic absorption 3, 4

Anticoagulation Therapy

• Approximately 70% of women on anticoagulants experience heavy menstrual bleeding 3
• Progestin-eluting IUDs are favored due to limited systemic absorption 3
• Re-evaluate necessity of ongoing antiplatelet agents and discontinue when clinically appropriate 3

Management of Breakthrough Bleeding

• If breakthrough bleeding occurs with extended COC regimens, a 3-4 day hormone-free interval can be taken, but not during the first 21 days of use and not more than once per month 1, 2
• NSAIDs for 5-7 days can be added for persistent heavy bleeding 1, 2
• Before treating breakthrough bleeding, rule out pregnancy, thyroid disorders, or new pathologic uterine conditions 2

Common Pitfalls to Avoid

• Always perform pregnancy testing before initiating any therapy, even in patients using contraception or with irregular cycles 3
• Do not rely solely on endometrial biopsy to exclude focal lesions; saline-infusion sonohysterography has 96-100% sensitivity for detecting uterine pathology 3
• Do not prescribe NSAIDs or tranexamic acid to women with cardiovascular disease without assessing thrombotic risk 3
• Ensure confidential discussion of contraceptive needs, as adolescents are significantly less likely to use family planning services without confidentiality assurances 2

When to Escalate Care

• Refer to gynecology if medical management fails after an adequate trial period (2-3 cycles) 3, 4
• Urgent evaluation is required when bleeding saturates a large pad or tampon for ≥4 hours 3
• Refer if endometrial sampling reveals hyperplasia or malignancy 3
• Consider hysteroscopy if bleeding persists despite therapy to exclude focal lesions missed by sampling 3, 4