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Objective:To evaluate the effect of human chorionic gonadotropins (hCG) and equine chorionic gonadotropins (eCG) on in vitro gilt oocyte maturation and embryonic development, using frozen semen for fertilization. Methods:Two independent experiments (6 replicates each) were carried out to evaluate gilt oocyte maturation, and fertilization and embryonic development by using ovaries from a local abattoir. Totally, 712 oocytes were randomly distributed in four-well dishes to receive Novormon (eCG 5.0 IU), PG600 (eCG 5.0 IU and hCG 2.5 IU), Chorulon (hCG 5.0 IU), or no hormones. Oocytes were incubated with 5％ CO2, 95％ air and saturation humidity at 39 ℃ for 44 h. Maturation of the oocytes to metaphaseⅡwas assessed by using the aceto-orcein technique. In addition, 741 oocytes were used and randomly distributed in four-well dishes, and then oocyte maturation was carried out as mentioned, but matured oocytes were washed and placed in fertilization medium with frozen-thawed sperm. Gametes were co-incubated for 7 h, and then washed and placed in development medium, and incubated for further 7 days, at which time embryonic development was evaluated. Fertilization and embryo development media were not supplemented with the studied hormones. Results:Novormon (eCG) and PG600 (eCG+hCG) treatments significantly improved the percentages of metaphaseⅡoocytes compared to the control group (P<0.05). Furthermore, a significant increase was also observed in the young blastocyst stage between the control group and the PG600 treatment group (P<0.05). Conclusions:Hormonal products Novormon (eCG) and PG600 (eCG+hCG) can obtain the highest percentages of in vitro maturation in gilt oocytes; however, this effect is not transferred to fertilization rates.