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The aim of this study was to be obtained pregnancy after the transfer of in vivo cattle embryos frozen by direct transfer method with ethylene glycol. First of all, 56 in vitro produced cow embryos of good quality were frozen by direct transfer method with ethylene glycol. After thawing, embryos were transferred into TCM-199 + 0.1 mM β-mercaptoethanol + 10% foetal calf Serum (FCS) medium to check in vitro survival at 24-48 h. The re-expansion and hatching rate of blastocysts was 64.28% (36 blastocysts). At the second stage; 8 good quality embryos were collected from superovulated culture breed cows. Embryos were equilibrated for 15 min in room temperature in 1.8M ethylene glycol + 0.1M sucrose in dulbecco's phosphate buffered saline (D-PBS) supplemented with 20% newborn calf serum (CS). Embryos were then loaded individually into a 0.25 ml straw and placed directly into a cooling chamber of a programmable freezer with methyl alcohol precooled to -7°C. After 2 min, straw was seeded, maintained at -7°C for 8 min more, and then cooled to -30°C either at 0.3°C/min before being into liquid nitrogen. The frozen embryos were thawed by allowing the straw to stand in air for 5 to 6 sec and then immersing them in a 30°C water bath. Embryos frozen-thawed in the presence of EG were nonsurgically transferred into the uterine horn into the recipient without diluting the cryoprotectant. Synchronized recipient cows with prostaglandine F2a were received one embryo each in the horn ipsilateral to the corpus luteum (CL). Pregnancies were diagnosed by rectal palpation 60 days after embryo transfer. Eight frozen-thawed embryos were transferred directly to eight recipients and five recipients gave birth to five normal calves. The pregnancy rate was 62.5%. This result indicated that EG can be used effectively for cattle embryo freezing and transfer as a suitable cryoprotectant. [ABSTRACT FROM AUTHOR]