Vaginal Progesterone Regimens for Endometrial Protection

Recommended Dosing Regimens

• The American College of Obstetricians and Gynecologists recommends prescribing 200mg vaginal progesterone daily for 12-14 days every 28 days for sequential dosing in women with an intact uterus on a 50mcg estradiol patch 1
• Expect withdrawal bleeding after each progestin cycle, which is a common outcome of sequential dosing regimens 2

Key Clinical Considerations

• Perform baseline transvaginal ultrasound before starting progestin to confirm appropriate endometrial thickness, as recommended by clinical guidelines 2

Important Caveats

• The Endocrine Society suggests using sequential dosing (200mg for 12-14 days/month) if the patient tolerates withdrawal bleeding and wants the most evidence-based approach 1
• For alternative regimens, the American College of Obstetricians and Gynecologists and the Endocrine Society recommend switching to oral micronized progesterone 200mg daily for 12-14 days every 28 days if the vaginal route is not tolerated 1, 3