Continuous Progesterone for Endometrial Protection Without Periods
Yes, taking progesterone continuously every day without having periods (amenorrhea) is a normal and medically appropriate regimen for endometrial protection when combined with estrogen therapy. 1, 2
Understanding Continuous vs. Sequential Regimens
There are two standard approaches to progesterone administration for endometrial protection, and both are medically appropriate:
Sequential (Cyclical) Regimen
- Progesterone is taken 12-14 days per month (typically 200 mg oral micronized progesterone daily) 3, 4
- This regimen induces withdrawal bleeding similar to a menstrual period each month 1, 2
- The bleeding occurs after stopping progesterone at the end of each cycle 5
Continuous Combined Regimen
- Progesterone is taken every single day without interruption (typically 100 mg oral micronized progesterone daily or 2.5 mg medroxyprogesterone acetate daily) 2, 5
- This regimen is specifically designed to induce amenorrhea (no periods) 2, 5
- Amenorrhea rates reach 88-93% by 3-6 months of continuous therapy 5
- This is the preferred approach for women who wish to avoid monthly bleeding 6, 5
Why Continuous Progesterone Causes Amenorrhea
The continuous presence of progesterone fully suppresses endometrial proliferation and prevents the buildup-and-shedding cycle that causes bleeding. 5 When progesterone is given daily at lower doses (100 mg vs. 200 mg for sequential regimens), it maintains the endometrium in a quiescent, non-proliferative state with inhibited mitoses, resulting in no withdrawal bleeding. 5
Endometrial Protection is Maintained
Both regimens provide complete endometrial protection against hyperplasia and cancer when used correctly: 3, 4
- Sequential regimen: 200 mg oral micronized progesterone for 12-14 days per month provides proven endometrial protection for up to 5 years 4
- Continuous regimen: 100 mg oral micronized progesterone daily (given 25 days per month or continuously) provides equivalent endometrial protection and induces amenorrhea in over 90% of women 5
- In clinical trials, only 6% of women on progesterone plus estrogen developed hyperplasia compared to 64% on estrogen alone 3
What to Expect with Continuous Progesterone
Initial spotting or bleeding is common but typically resolves: 5, 7
- During the first 3-6 months, irregular spotting or breakthrough bleeding may occur 8
- By 6-12 months, amenorrhea rates exceed 90% with minimal to no bleeding episodes 5, 7
- Isolated spotting episodes may occur in some women but do not indicate treatment failure 7
Critical Dosing for Continuous Regimens
The minimum effective doses for continuous progesterone regimens are: 2, 5
- Oral micronized progesterone: 100 mg daily continuously 2, 5
- Medroxyprogesterone acetate: 2.5 mg daily continuously 2
- Dydrogesterone: 5 mg daily continuously 2
These lower daily doses (compared to sequential regimens) are sufficient because the progesterone is present continuously without hormone-free intervals. 5
When to Be Concerned
Contact your healthcare provider if you experience: 3
- Heavy or persistent bleeding after the first 6 months of continuous therapy 8
- Any bleeding that seems abnormal or concerning to you 3
- Severe side effects such as extreme dizziness, blurred vision, or difficulty speaking 3
Annual clinical review is recommended to assess compliance, bleeding patterns, and symptom control, with no routine laboratory monitoring required unless specific symptoms arise. 2
Bottom Line
Your provider has prescribed continuous progesterone specifically to avoid monthly periods while maintaining complete endometrial protection. 2, 5 This is a standard, evidence-based approach that is preferred by many women who wish to remain amenorrheic during hormone therapy. The absence of periods on this regimen is the intended therapeutic outcome, not a cause for concern. 6, 5