OBJECTIVE: To evaluat the effects of a culture medium with glucose in the presence of glutamine on the development of mouse embryos. METHODS: Two-cell embryos recovered from ICR mice at 48 hrs after hCG injection (mated just after hCG injection) were cultured in DMEM (with 20% hFF) supplemented with or without glucose on the presence of glutamine. Embryos were cultured under three different glucose regimens: (1) 0 mM (control); (2) 0.5 mM (group I); or (3) 3.15 mM (group II), and were analyzed at 24, 48, 72 and 96 hours intervals. Chi-square test (x2-test) was used to compare values of groups. RESULTS: No differences were found in the number of embryos showing morula (control: 37.5%; group I: 51.0%; group II: 48.4%), blastocyst (control: 21.5%; group I: 33.3%; group II: 34.4%) and blastocyst and hatching or hatched blastocyst (control: 81.9%; group I: 83.3%; group II: 82.8%) between groups at 24 hrs, 48 hrs or 72 hrs respectively. However at 96 hrs, the number of hatched and attached blastocyst was significantly higher in group I (82.3%) and II (78.5%) than control (63.2%; P<0.05). CONCLUSION: The addition of glucose (0.5 mM) to the DMEM, as energy source, improved the rate of development of late stage embryos in mice.