Our History: Age of IVF

A quarter century ago, the first human child was conceived outside her mother’s body. This marked the dawn of a new procedure, which practically put an end to human infertility. One generation later the procedure, initially known as in-vitro fertilization (IVF), has grown into a wide array of techniques: Assisted Reproductive Technologies. These include Embryo Freezing, GIFT, ZIFT, ICSI, TESA, MESA, AH, as well as a wide array of PGD techniques: PBR, BB, FISH, PCR, etc…

ICSI (IntraCytoplasmic Sperm Injection), introduced about a decade ago, revolutionized the way human oocyte is fertilized. Apart from being able to treat the most severe cases of male infertility, it also significantly increases the number of normally fertilized oocytes. Wide acceptance of ICSI as a routine IVF procedure has led a way to the introduction of the next step in human infertility treatment: Preimplantation Genetic Diagnosis.

Our History: Age of PGD

PGD stands for Preimplantation Genetic Diagnosis, a new technique designed to test genetic background of preimplantation human embryos. Diagnosis of the genetic status of the embryos before a pregnancy is established has revolutionized the way human infertility and genetic disorders are being treated.

During regular IVF cycle, the “best-looking” embryos are selected for transfer to establish a pregnancy. PGD had shown that the embryo should be also genetically normal in order to ascertain a normal pregnancy and birth of a healthy child.

In order for PGD to be performed, one cell should be gently extracted from a 3-day old human embryo. This single cell is then analyzed for the presence of a specific genetic disorder.

Discovery of PCR technique for DNA amplification had made it possible to detect a mutant gene by analyzing a single human cell. The carriers of single-gene disorders were thus the first group of patients who received benefits of PGD.

Recent breakthrough in Fluorescent In-Situ Hybridization (FISH) technique and further advancements in single-cell fixation had made it possible to expand PDG for detection of not only single-gene disorders but also chromosomal abnormalities: aneuploidies, translocations, and inversions. This opened a new chapter in human PGD.

Down’s Syndrome (trisomy 21, or the presence of an extra chromosome 21) is the most common genetic defect in newborns. Each 100,000 pregnancies result in the birth of 100 boys with Kleinfelter’s Syndrome and 50 girls with Turner’s Syndrome. Combined, these are the second most common genetic abnormalities in humans. All standard PGD procedures for aneuploidy performed now test simultaneously for the correct number of sex chromosomes (XX for girls and XY for boys), as well as chromosomes 13 (trisomy 13 leads to Patau’s Syndrome), 18 (trisomy 18 is known as Edward’s Syndrome), and chromosome 21.

PGD procedures for aneuploidy usually test simultaneously for the correct number of 5 chromosomes: sex chromosomes (XX for girls and XY for boys), as well as chromosomes 13 (trisomy 13 leads to Patau's Syndrome), 18 (trisomy 18 is known as Edward's Syndrome), and chromosome 21.

At ViaGene Fertility, we perform PGD-aneuploidy screening for the correct number of up to 9 chromosomes: 13, 15, 16, 17, 18, 21, 22, X, and Y.