Cervical cerclage, pessary, or vaginal progesterone in high-risk pregnant women with short cervix: a randomized feasibility study. - Care, A.; Jackson, R.; O'Brien, E.; Leigh, S.; Cornforth, C.; Haycox, A.; Whitworth, M.; Lavender, T.; Alfirevic, Z. (Journal of Maternal-Fetal & Neonatal Medicine, 2021)