What is the recommended dose of vaginal progesterone (micronized progesterone) for recurring miscarriages?

Vaginal Progesterone Dosing for Recurrent Miscarriage

For women with recurrent miscarriage and early pregnancy bleeding, use vaginal micronized progesterone 400 mg twice daily (total 800 mg/day) starting as soon as pregnancy is confirmed and continuing until 12 weeks of gestation. 1, 2

Evidence-Based Dosing Recommendations

Primary Regimen for Recurrent Miscarriage with Bleeding

• Vaginal micronized progesterone 400 mg twice daily is the evidence-based dose for women with both recurrent miscarriage history AND current pregnancy bleeding 1, 2
• Treatment should begin immediately after positive pregnancy test and continue through 12 completed weeks of gestation 2, 3
• This regimen showed a 5% absolute increase in live birth rate (75% vs 70%) in women with prior miscarriage(s) and current bleeding 2

Alternative Lower-Dose Regimens

• 90-mg vaginal gel daily or 200-mg suppository daily are alternative options mentioned in guidelines, though these doses were studied primarily for preterm birth prevention rather than recurrent miscarriage 4, 1
• The 400 mg twice daily regimen has stronger evidence specifically for the recurrent miscarriage population with bleeding 2

Critical Clinical Context

When Progesterone IS Indicated

The evidence supports progesterone use specifically when both risk factors are present:

• History of one or more previous miscarriages AND
• Current pregnancy bleeding in first trimester 2
• The benefit increases with number of prior losses: women with ≥3 prior miscarriages showed 15% absolute improvement (72% vs 57% live birth rate) 2

When Progesterone Is NOT Recommended

• Recurrent miscarriage WITHOUT current bleeding: The PROMISE trial found no benefit (65.8% vs 63.3% live birth rate, not significant) 3, 5
• A 2025 Cochrane review confirmed probably little to no effect on miscarriage rate (RR 0.91,95% CI 0.76-1.07) or live birth rate (RR 1.04,95% CI 0.96-1.12) in women with recurrent miscarriage of unclear etiology 6
• The STOP trial similarly found no benefit in threatened miscarriage overall (82.4% vs 84.2% live birth rate) 7

Important Caveats

Route and Formulation Matter

• These recommendations apply specifically to vaginal micronized progesterone, not oral progesterone or intramuscular 17-hydroxyprogesterone caproate (17P) 1
• 17P 250 mg IM weekly is indicated for preterm birth prevention in women with prior spontaneous preterm birth, not for miscarriage prevention 4

Timing Is Critical

• Treatment must begin early—ideally immediately after positive pregnancy test and no later than 6 weeks gestation 3, 5
• Continue through 12 completed weeks of gestation 2, 3

Safety Profile

• No short-term safety concerns identified in large trials 2
• No significant differences in adverse events, preterm birth rates, or birth weights 3, 5, 7