What initial oral estrogen dose and accompanying progestogen regimen are recommended for a 47‑year‑old woman weighing 133 lb with an intact uterus?

Oral Estrogen Dosing for a 47-Year-Old Woman with Intact Uterus

For a 47-year-old woman weighing 133 lb with an intact uterus, start with oral 17β-estradiol 1 mg daily combined with oral micronized progesterone 200 mg daily for 12-14 days per 28-day cycle. 1, 2

Estrogen Component

• Oral 17β-estradiol is preferred over conjugated equine estrogens or ethinyl estradiol for hormone replacement therapy in perimenopausal women 3, 2
• Start with 1 mg oral 17β-estradiol daily, which can be titrated up to 2 mg daily if symptoms persist after 2-3 months 1, 2
• The typical maintenance dose range is 1-2 mg daily for optimal symptom control 2
• Transdermal 17β-estradiol (50-100 mcg patches twice weekly) is actually the superior first-line choice due to significantly lower cardiovascular and thrombotic risk compared to oral formulations, but since you specifically asked about oral dosing, oral estradiol 1-2 mg daily is the appropriate oral option 1, 4, 2

Required Progestogen for Endometrial Protection

Any woman with an intact uterus taking estrogen must receive progestogen to prevent endometrial hyperplasia and cancer. 1, 2, 5

First-Line Progestogen Regimen:

• Oral micronized progesterone 200 mg daily for 12-14 days per 28-day cycle (sequential regimen) 1, 5
• This sequential regimen will induce predictable withdrawal bleeding 1
• Micronized progesterone is preferred over synthetic progestins due to lower cardiovascular and thrombotic risk 1, 6

Alternative Progestogen Options (if micronized progesterone not tolerated):

• Dydrogesterone 10 mg daily for 12-14 days per month 1
• Medroxyprogesterone acetate 10 mg daily for 12-14 days per month 1, 4
• These are second-line options with less favorable metabolic profiles 1

Continuous Combined Alternative (to avoid withdrawal bleeding):

• Oral micronized progesterone 100 mg daily continuously paired with continuous estradiol 1
• Dydrogesterone 5 mg daily continuously paired with continuous estradiol 1
• Medroxyprogesterone acetate 2.5 mg daily continuously paired with continuous estradiol 1

Critical Dosing Principles

• Never use progestogen for fewer than 12 days per cycle in sequential regimens—this provides inadequate endometrial protection 1
• The FDA label data demonstrates that 200 mg micronized progesterone daily for 12 days per cycle reduced hyperplasia incidence to 6% versus 64% with estrogen alone over 3 years 5
• Start with the lowest effective dose and use for the shortest duration consistent with treatment goals 1

Monitoring and Follow-Up

• Annual clinical review focusing on compliance, bleeding patterns, and symptom control 1, 2
• No routine laboratory monitoring is required unless specific symptoms or concerns arise 1
• Adjust dose according to symptom control and patient tolerance 1

Common Pitfalls to Avoid

• Never prescribe estrogen alone in a woman with an intact uterus—this dramatically increases endometrial cancer risk (64% hyperplasia rate at 3 years) 5, 7
• Avoid ethinyl estradiol for hormone replacement therapy—it carries significantly higher thrombotic risk than bioidentical 17β-estradiol 2
• At age 47, this patient is perimenopausal (not postmenopausal), so ensure she understands this is hormone replacement therapy, not contraception—if pregnancy prevention is needed, consider alternative methods 3

Weight Considerations

• At 133 lb (approximately 60 kg), standard dosing applies without modification 3
• The transdermal patch shows slightly reduced efficacy in women over 198 pounds, but this patient is well below that threshold 3
• For obese women, transdermal estradiol would be preferred over oral due to lower VTE risk, but at 133 lb this is not a concern 6

Cardiovascular and Thrombotic Risk Context

• Risks such as venous thromboembolism, coronary events, and stroke occur within the first 1-2 years of therapy 1
• The Women's Health Initiative demonstrated that per 10,000 women taking estrogen-progestin for 1 year, there are 8 additional strokes, 8 more pulmonary emboli, and 7 more coronary events 7
• If this patient has cardiovascular risk factors, strongly consider switching to transdermal estradiol (50 mcg patches twice weekly) instead of oral, as transdermal has neutral VTE risk (OR 0.9) versus oral estradiol (OR 4.2) 2