Changes in Implantation and Survival Rates and Embryo Quality After Progesteron

Purpose: Determining the effect of progesterone on the embryo quality (total cell number and diameter of blastocyst), survival and implantation rates of mouse blastocyst with or without ovarian stimulation. Materials and Methods: Female 6-10 weeks old NMRI mice were divided into four groups as follows: (a) Non-stimulated pregnant mice as control (b) Non-stimulated pregnant mice with daily injection of progesterone 1) mg/mouse subcutainly after natural mating), (c) Stimulated pregnant mice that superovulated with an intraperitoneal injection of 10IU pregnant mare's serum gonadotrophin (PMSG), followed 48h later by another intraperitoneal injection of 10IU human chorionic gonadotrophin hormone (hCG), (d) Stimulated pregnant mice with injection of progesterone (1 mg/mouse subcutainly after hCG injection). All four groups were pregnant using natural mating. To collect the blastocyst, almost 17 pregnant mice in every four groups were sacrificed by cervical dislocation on day 4 of pregnancy. The total number of normal blastocyst and degenerated embryos were recorded. Also in other part of the study the implantation site were observed on day 7 of pregnancy in each group (near 15 pregnant mice) and compared with total number of blastocyst. Diameter of blastocyst was measured using calibrated eyepiece. After blastocyst staining with propidium iodide. The total cell numbers of blastocyst were counted. Results: The findings of this study showed that the survival and implantation rates of blastocyst in non-stimulated, non-stimulated with progesterone injection, hyperstimulated and hyperstimulated with progesterone injected groups were (92.25%-80.99%), (97.68%-92.06%), (85.17%-39.72%) and (87.25%-41.2%) respectively. The total cell numbers of blastocyst in studied groups were 87.37±1.4, 112±0.7, 128.62±1.3 and 126.88±1.6 respectively. There was significant differences in blastocyst survival and implantation rates in progesterone treated group (group 2) in comparison with the other group (p<0.05). Comparing the total cell numbers of blastocysts in studied groups, there was a statistical significatn increasing rate in both hyperstimulated grouops (p<0.001). Conclusion: The progesterone injection without ovarian induction could improve the implantation rate and embryo survival in comparison with the hyperstimulated groups.