11.   But although the chances of frozen embryos being viable are small, fertility experts say, patients and their doctors still cherish every one.

12.   But the ranks of frozen embryos raise a host of legal, emotional and ethical questions.

13.   But they argue that this debate is quantitatively different because the stem cells are derived from frozen embryos at fertility clinics that would otherwise be discarded anyway.

14.   Christian activists filed a lawsuit this year against the NIH on behalf of a California adoption agency that matches adoptive parents to frozen embryos.

15.   Dr. William E. Gibbons, who oversaw the work at the Jones Institute, said the procedure offered several advantages over using frozen embryos.

16.   Embryo adoption is the term used when a couple who are both infertile receive a spare frozen embryo created by another couple during their own in vitro fertilization.

17.   Even if scientists did want to use frozen embryos at fertility centers, there would be hurdles to overcome, Gibbons said.

18.   Hannah was created from frozen embryos.

19.   Hatch insisted that a frozen embryo stored in a refrigerator in a clinic was not equivalent to an embryo or a fetus in the womb.

20.   If all goes well and Mrs. Gemeny ends up with a baby, what would she do with the extra frozen embryos?