What are the uses of Prometrium (progesterone)?

Uses of Prometrium (Progesterone)

Prometrium (micronized progesterone) is primarily used for hormone replacement therapy in menopausal women, prevention of endometrial hyperplasia, treatment of secondary amenorrhea, and prevention of preterm birth in specific high-risk populations. 1, 2

Primary FDA-Approved Indications

1. Hormone Replacement Therapy

• Protection of the Endometrium: Used in combination with estrogen therapy in postmenopausal women with an intact uterus to prevent endometrial hyperplasia and reduce the risk of endometrial cancer 1
  • Dosage: 200 mg orally at bedtime for 12 continuous days per 28-day cycle 1

2. Secondary Amenorrhea

• Treatment of absence of menstrual periods in women who have previously menstruated but have stopped due to decreased progesterone production 1
  • Dosage: 400 mg orally at bedtime for 10 days 1

Additional Evidence-Based Uses

3. Prevention of Preterm Birth

• For women with singleton pregnancies and prior history of preterm birth
• For women with singleton pregnancies and short cervical length on ultrasound 3
• Vaginal progesterone (90-mg gel or 200-mg suppository) is recommended for women with singleton gestations, no prior preterm birth, and short cervical length (≤20 mm) at 24 weeks 3

4. Menopausal Symptom Management

• Effective for treatment of vasomotor symptoms (hot flashes and night sweats) 4
• Improves sleep quality in menopausal women 4
• Dosage: 300 mg at bedtime has shown effectiveness in clinical trials 4

5. Abnormal Uterine Bleeding

• Helps regulate intermenstrual bleeding and decrease heavy menstrual bleeding in women of reproductive age or who are perimenopausal 5

6. Premature Ovarian Insufficiency

• Component of hormone replacement therapy in young women with chemotherapy or radiation-induced premature ovarian insufficiency 3
• Natural micronized progesterone has a favorable cardiovascular profile compared to synthetic progestogens 3

Administration Routes and Formulations

1. Oral Administration

   • Standard route for Prometrium capsules
   • Take at bedtime with water while standing to reduce risk of dizziness 1

2. Vaginal Administration

   • Alternative route for certain indications like preterm birth prevention 3
   • May be used in combination with transdermal estrogen for menopausal symptoms with potentially fewer side effects 6

Important Safety Considerations

• Contains peanut oil - contraindicated in patients with peanut allergies 1

• Should not be used in women with:

  • Unusual vaginal bleeding
  • Current or history of certain cancers
  • History of stroke or heart attack
  • Current or history of blood clots
  • Current or history of liver problems 1

• When combined with estrogen, may increase risk of:

  • Heart attacks
  • Strokes
  • Breast cancer
  • Blood clots
  • Dementia (in women over 65) 1

Advantages of Micronized Progesterone vs. Synthetic Progestogens

• Natural micronized progesterone has:
  • Minimal impact on cardiovascular risk 7
  • Neutral or beneficial effect on blood pressure 3
  • Better safety profile regarding thrombotic risk 3, 7
  • May have lower breast cancer risk compared to synthetic progestogens 7, 4
  • Lacks androgenic and glucocorticoid activities 7

Clinical Pearls

• Prometrium should be taken at bedtime due to potential drowsiness and dizziness 1
• For endometrial protection, continuous combined regimens provide better protection than cyclical, sequential regimens 3
• Low-dose oral progesterone (100 mg/day) given for 25 days can effectively protect the endometrium and induce amenorrhea in most postmenopausal women 8
• Transdermal estrogen combined with oral micronized progesterone may represent an optimized hormone replacement therapy approach with fewer risks 7

Remember that the benefits and risks of Prometrium should be regularly reassessed, and patients should be monitored for side effects and efficacy of treatment.