Culture and vitrification of human preembryos

Sammanfattning: Despite improvements in stimulation protocols, culture media formulations and laboratory protocols, the success rates in human IVF remain disappointingly low. The ability to successfully cryopreserve supernumerary embryos in a given IVF cycle without losing significant embryo viability is essential to maximize the cumulative benefit of a given treatment cycle. Therefore, studies on culture, cryopreservation and gene expression of human embryos fertilized in vitro were performed. In these studies the impact of culture media on fertilization of human oocytes in vitro was investigated. Furthermore, the impact of growth factor supplementation to in vitro culture media and embryo survival and cryodamage after vitrification were studied. Using in situ hybridization and immunohistochemistry methods, the expression of genes in the human Fallopian tube, endometrium, and pre-implantation embryos and in human embryonic stem cells (hES) cells was studied. The findings can be summarized as follows: in vitro culture media has impact on normal fertilization. Supplementation of growth factors to in vitro culture media implicates a physiological role in regulating pre-implantation development. Vitrification of embryos is an effective way of cryopreservation. In situ hybridization, immunohistochemical and matrix assisted laser desorption/ionization time of flight mass spectrometry methods are versatile tools in reproductive medicine research. These findings will help to identify markers for embryo development and characterisation of hESC. Furthermore, knowledge obtained will give us tools to improve formulations of culture and cryopreservation media, which in turn might increase the overall results in IVF treatment and maximise the usage of hESC.