embryos

Katie McMahon and her husband realized the gravity of using in vitro fertilization, or IVF, to conceive when, years later, they needed to make a decision about their final four embryonic children frozen in time by cryopreservation.

The U.S. Conference of Catholic Bishops objected to a National Institutes of Health proposal to authorize federally funded research on part-human, part-animal embryos in comments submitted to the agency Sept. 2.