Overview Oral Progesterone for Prevention of Preterm Birth Status: Completed Trial end date: 2009-01-01 Target enrollment: Participant gender: Summary To evaluate whether daily oral micronized progesterone is effective in preventing recurrent spontaneous preterm birth (RSPB) and whether micronized progesterone use increases maternal serum progesterone levels. Phase: Phase 3 Details Lead Sponsor: Fetal Medicine FoundationTreatments: Progesterone