The human embryo consists of 46 chromosomes, and the increase or decrease in the number of chromosomes, defined as chromosomal aneuploidies, is the main reason in approximately 50% of the pregnancies in which the embryo fails to attach to the uterus or results in miscarriage after attachment.
Detection of chromosomal abnormalities is possible in embryos developed by in vitro fertilization methods using preimplantation genetic screening (PGS). In our center, next generation sequencing (NGS) technique, a very advanced genetic analysis method giving results with high accuracy, is used for the purpose of PGS. Using this technique, it is possible to select a chromosomally normal (euploid) embryo. High adherence (implantation), reduction in miscarriage rates and high continuing pregnancy rates can be achieved with the transfer of the euploid embryo to the uterus.
Although higher success rates are achieved with embryo transfer with normal chromosomal content, this rate is unfortunately not 100%, other cellular factors are also thought to affect pregnancy. One of the factors thought to affect pregnancy success is the mitochondria organelle, which is the energy source of the cell. Mitochondria is one of the most important vital organs of the cell and contains its own genetic material (DNA).
Recent studies demonstrate that the increased amount of mitochondrial DNA in the embryo shows an insufficient energy level of the embryo and may be related to the failure of attachment of the embryo to the uterus (Diez-Juan A, Rubio C et al. 2015).
With the MitoScore method, both the chromosomal structure and the energy adequacy of the embryo can be determined in the embryos applied NGS for genetic screening purposes. MitoScore method works integrated with NGS method.
What is MitoScore?
MitoScore procedure is a method that enables the determination of the energy status of the embryo. In this method, the amount of genetic material (mtDNA) of the mitochondrial organelles in the embryo is determined. As a result of the test, it was observed that the embryo with the most ideal MitoScore had a higher capacity to adhere to the uterus.
Therefore, it is recommended that the decision of which of the embryos to be transferred first among the embryos that were applied NGS for the purpose of PGS and found to be chromosomally normal should be determined according to the MitoScore result.
It should not be forgotten that embryos with high mitoScore, meaning that they have low energy efficiency by this test, still have the possibility of attaching to the uterus and resulting in a healthy birth.
MitoScore is one of the methods that allows to select the best among good embryos and enable couples to get healthy babies home in less time.