A recent research at Igenomix reveals substantial increase in IVF success rates for patients undergoing conception through IVF by employing Preimplantation Genetic Diagnosis (PGD) followed by Preimplantation Genetic Screening (PGS) for chromosomal abnormalities. PGD is recommended for patients who are carriers of single gene disorders and are at a high risk of having an affected child. It allows the selection of non-affected embryos before implantation in couples to ensure a healthy baby. PGD is generally performed on a small embryo biopsy prior to transfer during IVF cycle and it helps to identify which embryos are not at risk of developing single gene disorder. This genetic test can be performed during IVF treatment.
The implantation, spontaneous abortions and take-home baby rates were analysed before and after PGD, which appeared to be significantly improved after PGD. It was seen that implantation rate prior to PGD was only 7.2%, in contrast to 34.8% after PGD, suggesting an almost five-fold improvement. As expected, there was also significant reduction of spontaneous abortion rate, which was 72% before and 26.9% after PGD. Accordingly, this contributed to the more than two-fold increase in take-home baby rate after PGD, which was as high as 65.7% in PGD cycles compared with 27.9% without PGD.
However, Igenomix expert, Dr. Rajni Khajuria says, “There are 50% chances of having chromosomal aneuploidy in the normal embryos, which have been selected after PGD screening. This can cause IVF failure, miscarriage or birth of a child with chromosomal abnormalities. Employing PGS with MitoScore after PGD can help further select embryos which are also free from any chromosomal abnormality and have a better chance of implantation and achieving pregnancy in the single IVF cycle.”
Chromosomal abnormality is responsible for spontaneous miscarriages and can result in birth defects in live born babies. A numerical change in the number of chromosomes is called aneuploidy. The most common syndromes caused by chromosomal aneuploidies are Down syndrome, Edwards syndrome, and Patau syndrome. Aneuploidy is usually not inherited and can involve any chromosome; however, the likelihood of embryos being aneuploid increases with the age of the mother. Igenomix’s PGS is comprehensive analysis of all 24 chromosome types. PGS is performed on small embryo biopsy prior to transfer during IVF cycle to screen for numerical chromosomal abnormalities and identifies which embryos are chromosomally normal. PGS testing helps IVF physicians and patients decide which embryos to transfer.
PGS has improved the chances of reproductive success in the following cases:
- Advanced maternal age (35 years and above)
- Repetitive implantation failure (2 or more failure)
- Recurrent miscarriages (2 or more miscarriage)
- Male factor (sperm abnormalities)
Employing PGS with the added advantage of MitoScore after PGD can help to select healthy embryos and increase the ongoing pregnancy rate to 42.9%.
A study conducted by Igenomix found that comparative genomic hybridization is more effective than FISH for identifying chromosomally normal embryos, which may result in a higher clinical pregnancy rate and implantation rate after embryo transfer. It was also concluded that IVF patients using PGS along with blastocyst transfer improves IVF success.
Igenomix uses Next Generation Sequencing (NGS) which is an effective technique for the analysis of copy number variation in single cells or few cells as is required for PGS. A validation study with cell lines of known karyotype is performed in Igenomix laboratory to optimize library preparation, timing and diagnosis accuracy. Igenomix reports that PGS testing with NGS gives 99% accuracy.
Igenomix is a biotechnology company providing advanced services in reproductive genetics. Its consolidated experience and advanced research capabilities make it one of the world leaders in this field and guarantee the provision of effective solutions tailored to different infertility problems. It is present in Valencia (Spain), Miami, Los Angeles, New York, Mexico City, Sao Paulo, Dubai and Delhi, with a workforce of over 170 professionals.
Further information about the company at https://www.igenomix.co.in/.