What is the recommended dose of progesterone (a hormone) for postmenopausal women?

Progesterone Dosing for Postmenopausal Women

For postmenopausal women with a uterus taking estrogen therapy, the recommended progesterone dose is 200 mg oral micronized progesterone daily at bedtime for 12-14 consecutive days per 28-day cycle (sequential regimen), or 100 mg daily continuously for those wishing to avoid withdrawal bleeding. 1, 2

Sequential Regimen (With Withdrawal Bleeding)

Micronized progesterone is the preferred first-line progestogen due to its superior cardiovascular and thrombotic safety profile compared to synthetic progestins. 1

Standard Dosing Options:

• Oral micronized progesterone: 200 mg daily at bedtime for 12-14 days per 28-day cycle 1, 2, 3
• Vaginal micronized progesterone: 200 mg daily for 12-14 days per month (alternative route with equivalent endometrial protection) 1, 3

Alternative Synthetic Progestins (if micronized progesterone unavailable):

• Medroxyprogesterone acetate (MPA): 10 mg daily for 12-14 days per month 1, 4
• Dydrogesterone: 10 mg daily for 12-14 days per month 1
• Norethisterone: 5 mg daily for 12-14 days per month 5

Continuous Combined Regimen (Avoiding Withdrawal Bleeding)

For women who prefer amenorrhea:

• Oral micronized progesterone: 100 mg daily continuously 1, 6
• Medroxyprogesterone acetate: 2.5 mg daily continuously 1, 4
• Dydrogesterone: 5 mg daily continuously 1
• Norethisterone: 1 mg daily continuously 1

The continuous regimen with 100 mg micronized progesterone achieves amenorrhea in 91-93% of women by 3-6 months while providing complete endometrial protection. 6

Critical Duration Requirements

The 12-14 day duration for sequential regimens is non-negotiable—shorter durations provide inadequate endometrial protection and increase endometrial cancer risk. 1, 3 Studies demonstrate that 10-day regimens may be insufficient, while 12-14 days consistently prevent endometrial hyperplasia. 3, 7

Regimens using progesterone every 3 months (quarterly) can prevent new hyperplasia but cannot reverse existing hyperplasia and carry higher bleeding rates. 8 This approach is not recommended as standard practice.

Administration Guidelines

Progesterone capsules must be taken at bedtime in the standing position with a full glass of water. 2 This timing minimizes the common side effects of dizziness, drowsiness, and in rare cases, blurred vision or difficulty walking that occur within 1-2 hours of ingestion. 2

Progesterone capsules contain peanut oil and are contraindicated in patients with peanut allergy. 2

Estrogen Component Pairing

When prescribing progesterone for endometrial protection, pair with:

• Transdermal 17β-estradiol 50-100 μg daily (preferred route) 1
• Oral 17β-estradiol 1-2 mg daily (alternative) 5

Transdermal estradiol is preferred over oral formulations due to lower cardiovascular and thrombotic risk, particularly important given that stroke, venous thromboembolism, and coronary events occur within the first 1-2 years of hormone therapy. 5

Monitoring and Duration

• Annual clinical review focusing on compliance, symptom control, and reassessment of risks versus benefits 1
• No routine laboratory monitoring required unless specific symptoms arise 1
• Use the lowest effective dose for the shortest duration consistent with treatment goals 5

For women aged 50-79 years, per 10,000 women taking estrogen-progestin therapy for 1 year, expect 8 additional invasive breast cancers, 9 more strokes, 12 more deep venous thromboses, and 9 more pulmonary emboli, balanced against 6 fewer colorectal cancers and 5 fewer hip fractures. 5

Common Pitfalls to Avoid

• Never use progesterone for fewer than 12 days per cycle in sequential regimens—this is the most critical error leading to inadequate endometrial protection 1, 3
• Never use transdermal progesterone for endometrial protection—it does not provide adequate protection regardless of dose 3
• Do not prescribe progesterone-only therapy for vasomotor symptoms as first-line treatment; efficacy is inconsistent and inferior to estrogen-based therapy 9
• Avoid starting with high doses; no additional benefit exists and harm increases 1

Contraindications

Do not prescribe progesterone if the patient has: 2

• Peanut allergy
• Undiagnosed abnormal vaginal bleeding
• Current or history of breast cancer or other hormone-sensitive malignancies
• Active or recent (within 1 year) arterial thromboembolic disease
• Active venous thromboembolism
• Active liver disease
• Known or suspected pregnancy