Fig. 1. Flow chart showing screening, randomization, follow-ups, and protocol deviations.

IVF, in-vitro fertilization; ICSI, intracytoplasmic sperm injection; IVM, in-vitro maturation. a Woman had protocol deviation in at least one transfer. b Two women in the blastocyst group never had embryo transfer but had frozen blastocysts for the reasons of endometrial factor and personal issues, respectively; 1 woman in the cleavage group never had embryo transfer but had frozen cleavage-stage embryos for the reason of personal issues. c Among the 2 women with double cleavage-stage transfer, 1 woman had double cleavage-stage transfer in the fresh embryo transfer cycle and double blastocyst transfer in the second frozen embryo transfer cycle. d Among the 6 women with double blastocyst transfer, 1 woman had double cleavage-stage transfer in the fresh embryo transfer cycle, and double blastocyst transfer in the subsequent frozen embryo transfer cycle; 1 woman had one blastocyst transfer in the first frozen transfer cycle, and double blastocysts transfer in the second frozen transfer cycle.