Progesterone Dosing for Low Progesterone Levels
Introduction to Progesterone Regimens
- The American College of Obstetricians and Gynecologists recommends starting with micronized progesterone (MP) 200 mg orally or vaginally for 12-14 days every 28 days when used sequentially with estrogen, or 100-200 mg daily for continuous regimens for women with low progesterone requiring hormone replacement therapy 1, 2
Sequential Regimen
- Micronized progesterone is the preferred progestogen due to its superior cardiovascular and thromboembolism safety profile compared to synthetic progestins 2, 3
- Oral or vaginal micronized progesterone: 200 mg daily for 12-14 days every 28 days when combined with continuous estrogen therapy 1, 2
- Alternative dosing: 100 mg daily for 12-14 days per month is acceptable for lower-dose estrogen regimens 4
Alternative Progestins
- Medroxyprogesterone acetate (MPA): 10 mg daily for 12-14 days per month 1, 2
- Dydrogesterone: 10 mg daily for 12-14 days per month 2, 3
- Norethisterone: 5 mg daily for 12-14 days per month 4
Continuous Combined Regimens
- MPA: 2.5 mg daily continuously 2, 3
- Dydrogesterone: 5 mg daily continuously 2, 3
- Norethisterone: 1 mg daily continuously 2
Critical Timing Considerations
- Progestin should only be added after 2-3 years of estrogen-only therapy in pubertal induction, or when breakthrough bleeding occurs 4
- Confirm adequate endometrial thickness via ultrasound before initiating progestin 4
- In post-pubertal women with established cycles, begin progestin immediately with estrogen therapy 1, 2
Important Caveats
- Avoid progestins with anti-androgenic effects in women with low testosterone or sexual dysfunction, as they may worsen hypoandrogenism 2, 3
- Do not confuse different progesterone formulations: Injectable 17-alpha-hydroxyprogesterone caproate (17P) 250 mg IM weekly is specifically for preterm birth prevention, not for general progesterone replacement 5