FDA-approved interpreting physician certification boards have started issuing certificates that have an expiration date.

If an interpreting physician allows his board certification to expire, must he or she obtain recertification to continue interpreting mammograms?

No. With respect to the requirement in 21 CFR 900.12(a)(1)(i)(B)(1), FDA has always considered board certification to be an initial requirement that does not expire. FDA will accept an expired certificate as meeting this requirement.