Received November 24, 2022
Accepted July 24, 2023

We evaluated effects of crocin supplementation during culture of intact and half-destroyed four-cell mouse embryos. Outcomes were the rate of cleavage arrest, blastocyst formation, and blastocyst cell numbers. Methods: We used laser to create two zonal holes without blastomere destruction in Groups 1 (n=100) and 2 (n=100), and to destroy two of the four blastomeres in Groups 3 (n=150) and 4 (n=150). Embryos were cultured in groups of ten in drops of medium without (Groups 1 and 3) or with 20 μg/ml of crocin supplementation (Groups 2 and 4). Results: Embryos in Groups 1 and 2 had no difference in the rate of cleavage arrest (6.0% vs. 7.0%, respectively; P=0.774) or blastocyst formation (89.0% vs. 86.0%, respectively; P=0.521). Neither was there a difference in the number of cells in the blastocysts (99.6 ± 23.5 vs. 95.6 ± 28.2, respectively, P = 0.83). Half-destroyed embryos cultured in crocin supplemented medium (Group 4) had a lower rate of cleavage arrest (14.7% vs. 30.0%, P=0.001), and higher blastocyst formation (51.3% vs. 37.3%, P=0.015), than those in non-supplemented medium (Group 3). In blastocysts derived from half-destroyed embryos, there was no difference in the number of cells in ICM (14.5 ± 3.9 vs. 13.7 ± 2.9, P= 0.285), TE (45.2 ± 12.3 vs. 46.0 ± 13.3, P=0.764), or total cells (59.7 ± 12.2 vs. 59.7 ± 14.8, respectively, P=0.990) among the two groups. Conclusion: crocin supplementation during in vitro development of impaired embryos improved their development, but it had no effect on intact embryos.