American fertility clinics and their patients are moving embryos to guard against the possibility that some states might give legal protection to embryos, the Wall Street Journal reports.

Spokesmen for the lucrative assisted-reproduction industry explained that states could criminalize the destruction of frozen embryos that doctors said were not viable.

In 2019—the last year for which reliable data are available—more than 2% of the babies born in the US were the result of in vitro fertilization.