Zafarmand, M. H.Goossens, S. M. T. A.Tajik, P.Bossuyt, P. M. M.Asztalos, E. V.Gardener, G. J.Willan, A. R.Roumen, F. J. M. E.Mol, B. W.Barrett, Y. (Jon)Group, the Twin Birth Study CollaborativeTwin Birth Study Collaborative Group2021-05-182021-05-182021-04-01Zafarmand, M H, Goossens, S M T A, Tajik, P, Bossuyt, P M M, Asztalos, E V, Gardener, G J, Willan, A R, Roumen, F J M E, Mol, B W, Barrett, Y, Group, T T B S C & Twin Birth Study Collaborative Group 2021, 'Planned Cesarean or planned vaginal delivery for twins : secondary analysis of randomized controlled trial', Ultrasound in Obstetrics and Gynecology, vol. 57, no. 4, pp. 582-591. https://doi.org/10.1002/uog.219070960-7692RIS: urn:6B7F6BE36941068A3C71A6C3CCC3F7FBPubMedCentral: PMC8048696https://hdl.handle.net/2164/16487ACKNOWLEDGMENTS We thank all the participants in the Twin Birth Study and the staff at the Centre for Mother, Infant, and Child Research for their hard work and dedication. The Twin Birth Study was supported by a grant (63164) from the Canadian Institute of Health Research. P.T. and M.H.Z. were supported by a grant from The Netherlands Organization for Scientific Research (NWO ‐ grant number 401.16.080). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.10639425enggestational agemode of deliverymultiple pregnancytwinsR MedicineRJournal article10.1002/uog.21907574