In a patient switching from depot medroxyprogesterone acetate (Depo‑Provera) to daily 200 mg oral micronized progesterone combined with a low‑dose estrogen patch, does the progesterone suppress the menstrual cycle?

Oral Micronized Progesterone 200 mg Daily Does NOT Suppress the Menstrual Cycle When Switching from Depo-Provera

When transitioning from depot medroxyprogesterone acetate (Depo-Provera) to 200 mg oral micronized progesterone combined with a low-dose estrogen patch, the progesterone component alone will NOT suppress ovulation or menstruation—you are essentially switching from contraceptive-level progestin suppression to hormone replacement therapy that permits cycle resumption. 1

Understanding the Fundamental Difference in Progestin Dosing

The critical issue here is that Depo-Provera provides contraceptive-level progestin suppression (150 mg intramuscular medroxyprogesterone acetate every 12 weeks), which completely suppresses the hypothalamic-pituitary-ovarian axis and prevents ovulation. 2 In contrast, 200 mg daily oral micronized progesterone is designed for endometrial protection in hormone replacement therapy, NOT for cycle suppression or contraception. 1, 3

Key Mechanistic Points:

• Depo-Provera suppresses ovulation through sustained high progestin levels that inhibit the LH surge and follicular development 2
• 200 mg oral micronized progesterone produces adequate endometrial transformation to prevent hyperplasia when combined with estrogen, but does NOT reliably suppress ovulation 3, 4
• The bioavailability and pharmacokinetics of oral micronized progesterone result in tissue levels sufficient for endometrial protection but insufficient for consistent ovulatory suppression 3

What to Expect After the Switch

Cycle Resumption Timeline:

• Ovulation may resume within 2-4 months after the last Depo-Provera injection wears off, regardless of starting the progesterone/estrogen combination 2
• The 200 mg progesterone dose will induce withdrawal bleeding when given sequentially (12-14 days per month), but this is pharmacologically-induced bleeding, not suppression of natural cycles 1, 5
• If the patient has residual ovarian function, spontaneous ovulation and menstruation may occur once Depo-Provera effects dissipate 2

Bleeding Pattern Expectations:

• Sequential regimen (200 mg progesterone for 12-14 days per month): Expect predictable withdrawal bleeding after each progesterone phase 1, 5
• Continuous regimen (100 mg progesterone daily without interruption): Induces amenorrhea in 80-93% of postmenopausal women by 3-6 months, but this is NOT the same as ovulatory suppression 5, 6
• Breakthrough bleeding may occur in the first 3-6 months as the endometrium adjusts 5, 6

Critical Clinical Caveat: Contraception Requirement

If contraception is needed, this regimen is inadequate. 2, 1 The combination of low-dose estrogen patch plus 200 mg oral micronized progesterone is hormone replacement therapy, not birth control. 1

If Contraception Is Required:

• Continue Depo-Provera (safe and effective contraceptive method) 2
• Switch to a progestin IUD (levonorgestrel IUD provides both contraception and endometrial protection) 2
• Use combined oral contraceptives containing 17β-estradiol with nomegestrol acetate or dienogest as first-line options 1
• Add barrier methods if the patient insists on switching to HRT-level dosing 2

Recommended Regimen Structure

For Sequential Hormone Replacement (Permits Withdrawal Bleeding):

• Transdermal 17β-estradiol 50-100 mcg/day applied continuously (patch changed twice weekly) 1, 7
• Oral micronized progesterone 200 mg daily for 12-14 days every 28-day cycle 1, 3
• This regimen provides endometrial protection but does NOT suppress ovulation 3, 4

For Continuous Combined Regimen (Induces Amenorrhea):

• Transdermal 17β-estradiol 50-100 mcg/day applied continuously 1, 7
• Oral micronized progesterone 100 mg daily without interruption 1, 5
• Amenorrhea occurs in 80-93% by 6 months, but this is endometrial quiescence, not ovulatory suppression 5, 6

Common Pitfall to Avoid

Do NOT assume that 200 mg oral progesterone provides contraceptive protection simply because Depo-Provera did. 2, 1 The doses and pharmacokinetics are entirely different:

• Depo-Provera: 150 mg IM every 12 weeks = sustained contraceptive-level suppression 2
• Oral micronized progesterone 200 mg daily = endometrial protection only, NOT contraception 1, 3, 4

Monitoring After Transition

• Assess bleeding patterns monthly for the first 3-6 months to distinguish withdrawal bleeding from breakthrough ovulatory bleeding 1, 5
• Annual clinical review focusing on compliance, bleeding patterns, and symptom control 1, 7
• No routine laboratory monitoring required unless specific symptoms arise 1, 7
• Counsel on contraception needs explicitly before making the switch 2, 1