Preimplantation Genetic Screening (PGS)
Unlike carrier screening and PGD, PGS looks at the chromosome content of each embryo. A healthy person is born with 46 chromosomes, 23 that they inherited from their mother and 23 from their father. A portion of all embryos will have too many or too few chromosomes, usually as a result of decreasing egg quality as women age. These abnormal embryos will either not implant, or rarely end in an early miscarriage, or even rarer develop into a child that may have a chromosomal disorder such as Down Syndrome (an extra copy of chromosome 21) or Turners Syndrome (a missing copy of the X chromosome). When a couple does IVF they have the option of utilizing PGS, where the are biopsied and a small number of cells sent to a genetics laboratory where they can analyze the chromosome content of each embryo. This allows us to select the embryo/s that will have the highest chance of a leading to a healthy baby.