Mouse embryo development following IVF in media containing either L-glutamine or glycyl-L-glutamine.

BACKGROUND The development of the mouse zygote following fertilization in vitro in a KSOM-type medium containing either L-glutamine or glycyl-L-glutamine has been examined, and compared with the development of mouse zygotes produced by natural fertilization. METHODS Mouse IVF, embryo culture and embryo transfer. RESULTS Fertilization rates, development to the blastocyst stage, implantation rate, gross fetal development and fetal body weight are not different in a KSOM-type medium containing either L-glutamine or glycyl-L-glutamine. No evidence of abnormal fetal development, such as exencephaly, was observed. The replacement of L-glutamine with glycyl-L-glutamine favoured the development of relatively more inner cell mass cells than trophectoderm cells, and reduced the numbers of pyknotic and fragmented nuclei in the blastocysts that developed in vitro. CONCLUSIONS There is no evidence that the presence of glutamine in the medium used for IVF influences significantly the subsequent development of the zygote. Replacing glutamine with glycyl-L-glutamine may be advantageous.