Guidance on the limits to the number of embryos to transfer: a committee opinion.

On the basis of American Society for Reproductive Medicine and Society for Assisted Reproductive Technology data, the American Society for Reproductive Medicine's guidelines for the limits on the number of embryos to be transferred during in vitro fertilization cycles have been further refined in continuing efforts to promote singleton gestation and reduce the number of multiple pregnancies. This version replaces the document titled "Criteria for number of embryos to transfer: a committee opinion" that was published most recently in August of 2017 (Fertil Steril 2017;107:901-3).