Related by context. Frequent words. (Click for all words.) 71 unfertilized eggs 67 gametes 65 oocytes 64 unfertilized egg 64 oocyte 62 fertilized eggs 61 gamete 60 unfertilized human 59 Embryos 59 embryos 59 cloned embryo 59 ovary 58 embryo 58 cryopreserved 58 ovarian tissue 58 unused embryos 58 oviduct 58 somatic cell 58 eggs 57 undifferentiated cells 57 ovum 57 IVF embryos 57 sperms 57 mouse embryos 56 leftover embryos 56 somatic cells 56 pluripotent cells 56 germ cells 56 ovaries 55 umbilical cord stem cells 55 Artificial insemination 55 sperm 55 blastocyst 55 fertilized egg 54 fertilized embryos 54 vaginal secretions 54 spermatozoa 54 pancreases 54 myoblasts 54 cloned embryos 54 blastocysts 54 cloned stem cells 53 genital organs 53 ova 53 hermaphrodites 53 fibroblast cells 53 stem cells 53 testes 53 extract stem cells 52 imprinted genes 52 Embryo 52 ovulate 52 pupa 52 ovulated 52 vitro fertilization clinics 52 Therapeutic cloning 52 genetically identical 52 fetal stem cells 51 ovarian function 51 transgenic mouse 51 corms 51 fetal tissue 51 somatic cell nuclear 51 genetically manipulated 51 diploid 51 ethically acceptable 51 egg 51 ovarian stimulation 51 pipefish 50 infertile 50 embryonic cells 50 follicle stimulating hormone 50 granulocytes 50 pluripotent stem cells 50 regenerate tissue 50 lobules 50 pistil 50 blastocyst stage 50 follicles 50 rhesus macaques 50 transplanted tissue 50 teratomas 50 hematopoietic stem cells 49 neonate 49 plantlets 49 islet cells 49 frozen semen 49 preventing ovulation 49 ejaculates 49 Adult Stem Cells 49 gonad 49 chimeras 49 umbilical cords 49 pancreatic islet cells 49 pupae 49 stromal cells 49 ES cells 49 asexual reproduction 49 mouthparts 49 neural stem cells 49 donor sperm