Related by context. Frequent words. (Click for all words.) 66 embryo 63 oocyte 63 umbilical cord stem cells 61 embryos 60 somatic cell 60 unfertilized egg 58 transplanted tissue 58 gametes 58 sperm 58 embryo implantation 58 stem cells 57 oocytes 57 undifferentiated cells 57 unfertilized eggs 57 cryopreserved 56 preimplantation genetic diagnosis 56 pluripotent cells 56 ovum 56 fetal tissue 56 fertilized embryos 56 mouse embryos 55 fetal stem cells 55 IVF treatment 55 somatic cells 55 cloned embryo 54 fertilized eggs 54 fertilized egg 54 granulocytes 54 ovarian tissue 54 sperms 53 donor sperm 53 embryo transfers 53 leftover embryos 53 cloned stem cells 53 Embryos 53 bone marrow stem cells 53 extract stem cells 53 blastocyst 52 frozen embryo 52 bone marrow transplants 52 Blood transfusions 52 IVF 52 spermatozoa 52 amniotic fluid 52 Embryo 52 cloned embryos 51 chorionic villus sampling 51 rhesus 51 pancreatic islet cells 51 embryonic cells 51 undergoing IVF 51 bone marrow stem cell 51 transplanted stem cells 51 donor insemination 51 RPE cells 51 bone marrow 51 ESCs 51 myoblasts 51 pancreases 51 unfertilized human 51 hyaluronidase 50 Transfusions 50 cell transplantation 50 transplanted organ 50 tissue 50 pluripotent stem cells 50 placentas 50 uterus 50 germ cells 50 RBCs 50 ova 50 ovary 50 vitro fertilization IVF 50 diseased tissues 50 transplanted kidneys 50 ex vivo 50 hormone progesterone 50 Umbilical cord blood 50 newborn infants 50 umbilical cord blood 49 progenitor cell 49 somatic cell nuclear 49 anonymous sperm donor 49 weeks gestation 49 ovaries 49 synthetic genome 49 follicles 49 Fallopian tubes 49 Therapeutic cloning 49 Adult Stem Cells 49 blastocysts 49 stem cell 49 vitro fertilization 49 antithrombin 49 leukocyte 49 germline 49 IVF treatments 49 immunosuppressant drugs 49 endothelial progenitor cells 49 unused embryos 48 artificial insemination