Related by context. Frequent words. (Click for all words.) 64 embryo 62 embryos 60 human embryos 56 oocytes 56 stem cells 56 adult stem cells 55 somatic cell nuclear 55 embryonic cells 54 umbilical cord blood 53 destroying embryos 53 fertilized eggs 53 stem cells derived 53 placentas 52 frozen embryos 52 embryonic stem cell 52 embryonic stem cells 52 cloned embryos 51 aborted fetuses 51 stem cell 51 fetuses 51 sperm 50 umbilical cords 50 tissue 49 organs 49 fertilized egg 49 fetus 49 therapeutic cloning 49 human cloning 49 Embryos 49 ovarian tissue 48 fertility treatments 48 cloning 48 reproductive cloning 47 adult stem cell 47 human embryonic stem 47 vitro fertilization 47 fetal 47 embryonic 46 islet cells 46 unborn babies 46 ova 46 pluripotent stem cells 46 cord blood 45 stem cell research 45 amniotic fluid 45 IVF 45 neural stem cells 45 abortions 45 semen 45 tissue samples 45 fertility clinics 45 bioethicists 44 ovaries 44 livers 44 tissues 44 bone marrow stem cells 44 germ cells 44 abortion 44 rBGH 44 ovary 44 mifepristone 44 organ transplants 44 assisted reproduction 43 Fetal 43 induced pluripotent stem cells 43 tubal ligation 42 cadavers 42 partial birth 42 amniocentesis 42 ES cells 42 contraceptives 42 vitro 42 liver 42 ex vivo 42 Stem cell 42 allograft 42 testis 42 informed consent 41 assisted reproductive 41 grafts 41 unborn 41 PGD 41 stem cell therapies 41 mesenchymal stem cells 41 uterus 41 vitro fertilization IVF 41 HFEA 41 unpasteurized milk 41 stem cell therapy 41 infertile couples 40 transplantation 40 autologous 40 organ transplantation 40 placenta 40 implantation 40 transplants 40 cadaver 40 eggs 40 artificial insemination 40 genetic modification 40 ethicists