Table 1.

PROMISE trial: vaginal micronized progesterone in women with unexplained recurrent miscarriages

Population	Women with unexplained recurrent miscarriages (≥3 consecutive or nonconsecutive miscarriages), trying to conceive naturally
Intervention	400 mg of micronized progesterone taken vaginally twice daily from no later than 6 weeks until 12 weeks of gestation
Comparison	Placebo
Primary outcome	Live birth beyond 24 weeks
Sample size and power	836 patients randomized; 90% power to detect a 10% difference in live births
Hospitals and countries	36 hospitals in the United Kingdom and 9 hospitals in the Netherlands

PROMISE, PROgesterone in recurrent MIScarriagE.

Coomarasamy et al. Micronized vaginal progesterone to prevent miscarriage: a critical evaluation of randomized evidence. Am J Obstet Gynecol 2020.