What are the treatment options for late menstruation?

Treatment Options for Late Menstruation

For late menstruation (secondary amenorrhea), progesterone therapy is the recommended first-line treatment, with 400 mg taken daily at bedtime for 10 days to induce menstrual bleeding. 1

Diagnostic Approach

Before initiating treatment, it's important to determine the underlying cause of late menstruation:

• Rule out pregnancy with a pregnancy test (most common cause)
• Check hormone levels including:
  • Follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
  • Thyroid-stimulating hormone (TSH)
  • Prolactin
  • Estradiol

Secondary amenorrhea is defined as the cessation of regular menses for three months or irregular menses for six months 2. The most common causes include:

• Polycystic ovary syndrome (PCOS)
• Hypothalamic amenorrhea (often stress-related)
• Hyperprolactinemia
• Primary ovarian insufficiency
• Thyroid disorders

Treatment Algorithm

1. Progesterone Therapy

• First-line treatment: Progesterone capsules 400 mg daily at bedtime for 10 days 1
• Take at bedtime due to potential side effects of drowsiness and dizziness
• Will induce withdrawal bleeding if adequate estrogen is present

2. Hormonal Options Based on Cause

For Hypothalamic Amenorrhea:

• Sequential use of estrogen and progestogen to prevent estrogen deficiency 3
• Combined oral contraceptives if contraception is also desired

For Hyperprolactinemic Amenorrhea:

• Prolactin-lowering drugs (dopamine agonists)
• Cyclical progestogen or hormone replacement therapy for cycle regulation 3

For PCOS:

• Combined oral contraceptives (especially beneficial for those with acne/hirsutism)
• Cyclical progestogen administration 3
• Consider metformin for insulin resistance

For Primary Ovarian Insufficiency:

• Hormone replacement therapy to prevent long-term consequences of hypoestrogenism 3

Special Considerations

For Women Desiring Pregnancy:

• For hypothalamic dysfunction: Consider referral for ovulation induction with pulsatile GnRH or gonadotropins 3
• For PCOS: Ovulation induction may be needed but has less favorable response 3

For Women Requiring Contraception:

• Combined hormonal contraceptives (failure rate 5-9%)
• Progestin-only pills (failure rate 5-9%)
• Levonorgestrel-releasing IUD (LNG-IUD) (failure rate 0.1-0.2%) - also reduces menstrual bleeding 4
• Depot medroxyprogesterone acetate (DMPA) (failure rate 0.3-6%) - may affect bone mineral density 4

Follow-up Recommendations

• Referral to gynecology/reproductive medicine/endocrinology is recommended for persistent menstrual cycle dysfunction 5
• For post-pubertal women with menstrual cycle dysfunction suggesting premature ovarian insufficiency, specialized referral is particularly important 5
• Assessment of response to treatment after 3 months 4

Important Cautions

• Progesterone capsules contain peanut oil and should not be used in patients with peanut allergies 1
• Progestins with estrogens should not be used to prevent heart disease, heart attacks, strokes, or dementia 1
• Take progesterone at bedtime as some women experience significant drowsiness, dizziness, blurred vision, or difficulty speaking 1
• For young patients (under 16), different criteria apply for evaluation of primary amenorrhea 5

By following this structured approach, most cases of late menstruation can be effectively managed with appropriate hormonal therapy while addressing the underlying cause.