Medroxyprogesterone for Amenorrhea: Dosage and Administration
For treating amenorrhea, medroxyprogesterone acetate (MPA) should be administered at a dose of 10 mg daily for 12-14 days per month to induce withdrawal bleeding. 1
Dosage Recommendations
- For patients with amenorrhea requiring withdrawal bleeding, MPA 10 mg daily for 12-14 days per month is the recommended regimen 1
- When used as part of sequential hormone therapy with estradiol, MPA is administered during the last 12-14 days of a 28-day cycle 1
- For continuous regimens (when withdrawal bleeding is not desired), a lower dose of 2.5-5 mg MPA daily can be used 1
Administration Approach Based on Clinical Context
For Secondary Amenorrhea (Without Estrogen Therapy)
- Administer MPA 10 mg daily for 5-10 days 2
- Withdrawal bleeding typically occurs within 3-7 days after completing the progestin course 2
- This approach is primarily diagnostic to confirm endometrial responsiveness and adequate endogenous estrogen levels 1
For Amenorrhea in Premature Ovarian Insufficiency (With Estrogen)
- Transdermal estradiol (50 μg daily) administered continuously with MPA 10 mg daily for 12-14 days every 28 days 1
- This sequential regimen induces regular withdrawal bleeding 1
- Continuous combined regimens (daily estrogen plus daily MPA 2.5-5 mg) can be used when amenorrhea is preferred 1, 3
Factors Affecting Treatment Success
- Endometrial thickness significantly correlates with bleeding response to progestin therapy 2, 4
- Adequate endogenous estrogen levels are required for successful withdrawal bleeding with progestin-only therapy 2
- In patients with very thin endometrium, estrogen priming before progestin administration may be necessary 4
Monitoring and Expected Outcomes
- Withdrawal bleeding typically occurs within 2-7 days after completing the progestin course 2, 5
- With sequential regimens, 80-93% of women will experience withdrawal bleeding 2, 6
- With continuous combined regimens, amenorrhea rates increase progressively over time, reaching 40-73% by 6-12 months 3, 5
Common Pitfalls and Considerations
- Absence of withdrawal bleeding after progestin challenge may indicate insufficient endogenous estrogen or endometrial pathology 1
- MPA has fewer side effects compared to some other progestins and does not significantly affect lipid profiles 2
- For patients requiring contraception alongside treatment for amenorrhea, combined hormonal contraceptives may be preferable to MPA alone 1
- In patients with iatrogenic premature ovarian insufficiency, micronized progesterone may be preferred over MPA due to potentially lower cardiovascular risk 1