Preimplantation Genetic
Screening Overview

Helping Families Conceive and Deliver Healthy Babies

Some Reasons You May Consider PGS:

  1. You want to optimize your IVF cycle, to select the embryos with the highest likelihood of implanting
  2. You have experienced multiple miscarriages
  3. You have had a pregnancy with a chromosome abnormality
  4. You have had several unsuccessful IVF cycles
  5. You or your partner carry a balanced structural chromosome rearrangement
  6. You want to balance the gender in your family

Background on Chromosome Abnormalities

There are 23 pairs of chromosomes (for a total of 46 chromosomes) in most cells of the human body. Chromosomes contain the genetic information that tells the body how to grow and develop. Half of the chromosomes are inherited from the egg and half are inherited from the sperm. The presence of extra or missing chromosomes is called aneuploidy. Embryos that have extra or missing chromosomes often develop improperly, are less likely to implant and are more likely to miscarry. Most of these pregnancies miscarry by the end of the first trimester, but some chromosomally normal pregnancies can continue and cause disorders in live-born babies.

Down syndrome, caused by an extra copy of chromosome 21, is the most commonly seen aneuploidy in live-born babies, although there are other aneuploidies that can result in more serious syndromes and can also be carried to term. Every couple will produce some embryos that have chromosome abnormalities. The rate increases as the woman gets older. With PGS testing, embryos are screened for extra or missing chromosomes, and those found to be chromosomally normal are preferentially transferred to the uterus for implantation.

The expectation is that, by screening for extra or missing chromosomes prior to embryo transfer:

  1. The chance of implantation and pregnancy can be increased.
  2. The chance for miscarriage can be decreased.
  3. The chance for a live birth with normal chromosomes can be increased.

PGS Services at PacGenomics

  • 24 chromosome PGS for IVF

    Our aneuploidy screening platforms are comprehensive tests that examines all 24 chromosomes including autosomes 1-22, and the sex chromosomes (X, Y).

  • Detecting Unbalanced Translocation for IVF

    An unbalanced translocation occurs when an embryo inherits a chromosome with extra or missing genetic material from a parent with a balanced translocation. Unbalanced translocations often result in miscarriage, or can lead to the birth of a child with intellectual disability and/or birth defects. Our microarray platform is optimized to detect chromosomal deletions and duplications larger than 1.8-3Mb in size, and to our knowledge, is the most sensitive test clinically available today.

Genetic Counseling

If you’d like learn more, you are welcome to speak to our in-house genetic counselor about your specific case.

Please be sure to have your IVF clinic first send in a referral form, so that the genetic counselor can best tailor the discussion to your individual needs.