Objective: To evaluate the effect of supplementing single-step embryo culture medium with insulin on human embryo development.
Design: Comparative study.
Setting: Two private centers.
Patient(s): The study involved a sibling oocyte split of 5,142 retrieved oocytes from 360 patients.
Intervention(s): Sibling oocytes split after intracytoplasmic sperm injection for culture from day 0 through day 5 or 6 in
insulin-supplemented or control medium. Women were split to receive their embryos from insulin-supplemented or control medium.
Main Outcome Measure(s): Clinical pregnancy rate.
Result(s): There were significantly higher rates of clinical, ongoing, and twin pregnancies in the insulin-supplemented arm than in the
control arm. On day 3, embryo quality and compaction were higher in insulin-supplemented medium. On day 5, insulin
supplementation showed higher rates of blastocyst formation, quality, and cryopreservation.
Conclusion(s): Insulin supplementation of single-step embryo culture medium from day 0 through day 5 or 6 improved clinical
pregnancy rate and human embryo development. However, these findings need further confirmation through a multicenter
randomized controlled trial that may include other patient populations and different culture media. (Fertil Steril 2017;107:405–12.
2016 by American Society for Reproductive Medicine.)
Key Words: Embryo culture media, insulin embryonic effect, blastocyst