The American Society for Reproductive Medicine (ASRM) guidelines for the limits on the number of embryos to be transferred in in vitro fertilization (IVF) cycles have been revised in an effort to promote singleton gestation and reduce the number of multiple pregnancies.

In patients with a favorable prognosis, the following guidelines for the number of embryos to be transferred in IVF cycles are recommended:

• In patients of any age, transfer of a euploid embryo had the most favorable prognosis and should be limited to 1.
• Patients aged <35 years should be encouraged to receive a single-embryo transfer, regardless of the embryo stage.
• For patients aged 35 to 37 years, strong consideration should be made for a single embryo transfer.
• For patients aged 38 to 40 years, no more than 3 cleavage-stage embryos or 2 blastocysts should be transferred. In cases where euploid embryos are available, a single blastocyst embryo transfer should be norm.
• Patients aged 41-42 years should plan to receive no more than 4 cleavage-state embryos or 3 blastocysts. In cases where euploid embryos are available, a single blastocyst transfer should be the norm.

The revised guidelines also address additional scenarios, including recommendations for patients who do not meet criteria for a favorable prognosis.