Mitochondrial DNA 4977 Bp Deletion And Content In Diminished Ovarian Reserve Patients' Unfertilized Oocytes

OBJECTIVE:To study the effects of diminished ovarian reserve on the outcome of IVF-ET;and explore the impaction of mtDNA4977bp deletion and mtDNA content on reproductive potential of DOR patients.METHODS:The study was carried out between March and September 2008 at the Reproductive Center of Xiang Ya hospital.We enrolled 80 infertility patients.According to the ovarian reserve,they were divided into two groups,DOR group and NOR group.On the day of embryo-transfer,110 unfertilized MII oocytes were collected,46 oocytes in DOR group,and 64 in NOR group.MtDNA4977bp deletion was detected by PCR;mtDNA content was quantified by real-time PCR. Analyse the IVF-ET outcome of the two groups.And compare the difference of mtDNA 4977bp deletion rate and mtDNA content between the two groups' oocytes.RESULTS:1,DOR patients showed significantly lower retrieved oocytes (6.57±3.59 vs 20.02±8.40;P＜0.05),good-embryo(2.77±1.83 vs 7.38±4.10;P＜0.05),fertilization rate(60.91%vs 69.03%;P＜0.05) and clinical pregnancy rate(6.67%vs 50%;P＜0.05),while significantly higher Gn dosage(38.70±10.74 vs 26.81±8.59;P＜0.05).The two groups' endometria thickness(9.99±2.19 vs 10.88±2.09;P＞0.05),the positive rate of three line(50%vs 46%;P＞0.05) and good-embryo rate (75.46%vs 67.58%;P＞0.05) showed no significant difference.2,DOR patients showed significantly higher mtDNA 4977bp deletion rate(48.8%vs 18.8%,p＜0.001).3,DOR patients showed significantly lower mtDNA content(9.96×10~4±5.21×10~4 vs 1.77×10~5±7.27×10~4 vs 18.8%,p＜0.001).CONCLUSION:1,The decreased developmental potential of oocyte may be connected with DOR patients' poor IVF-ET treatment outcome.2,The high mtDNA4977bp deletion rate and low mtDAN content in DOR patients' oocyte may be related to their decreased oocyte developmental potential.