PGD

 

For couples considering  IVF who are concerned about passing on an inherited genetic disease to their children, PGD is an excellent treatment option at Boston IVF. Preimplantation genetic diagnosis (PGD) is a procedure whereby individual cells are biopsied from the patient's embryos before they are transferred back into the uterus. The intention of performing the embryo biopsy is to select against embryos which may be chromosomally or genetically abnormal -- as well as to improve implantation rates.

Common single gene mutations that have been diagnosed with PGD and PCR include but are not limited to:

  • Cystic Fibrosis
  • Beta-Thalassemia
  • Sickle Celle Anemia
  • Tay-Sachs disease
  • Myotonic Dystrophy
  • Huntington's Chorea
  • Fragile X
  • Duchenne's Muscular Dystrophy

  

HOW PGD WORKS

PGD requires obtaining generic material  from an egg or an embryo -- and there are two types of biopsies performed. Polar body biospy enables the assessment of the genetic complement of the egg and provides indirect information of the genetic status of the egg in conditions where a genetic disorder is of material origin. Blastomere biopsy involves removing one or two cells from an early embryo, providing genetic information of maternal or paternal origin (if either parent is a carrier of a disorder) -- as well as information specific to that embryo (spontaneous mutations and sex).  

Several techniques are employed to identify the genetic abnormalities. Polymerase chain reaction (PCR) is the method used to detect single gene mutations and involves isolation and amplification of short DNA fragments.

Fluorescent In-Situ Hybridization (FISH) is a technique to determine abnormalities in the chromosomes within a particular blastomere. Fluorescently labeled probes that recognize specific sequences of a specific chromosome are allowed to hybridize to the cell. The cell may then be analyzed  under a fluorescent microscope to identify the presence or absence of the particular chromosome(s) in question. This technique is employed to evaluate embryos of patients who are carriers of a numerical chromosomal abnormality -- as well as for assessment of aneuploidy that occurs more frequently as a result of reproductive aging.

 

 

PGD CLINIC AT BOSTON IVF

Boston IVF offers PGD to couples for the following indications: 

  • Screening for single gene mutations and X-linked disorders in at-risk couples
  • Screening patients who are carriers of a numerical chromosome abnormality
  • Aneuploidy screening for patients with: advanced maternal age 40 and older, age 35 or greater and/or 3 failed IVF cycles -- or history of recurrent, spontaneous miscarriage (three or more) 

Most individuals and couples seeking PGD are already aware of a genetic disorder and have undergone testing to verify it. If testing is necessary to identify a genetic disorder, we will work with you to set up an appointment with a genetic counselor  to schedule the appropriate testing.

The first step for patients interested in PGD treatment at Boston IVF is to schedule a consultation with a Boston IVF physician.  At this consultation you will describe the process and discuss your options.

Once both you and your  physician have determined that you are a candidate to participate in Boston IVF's PGD program, they will then outline the steps required before a PGD/IVF cycle may start. They include:

  • Your Boston IVF physician will notify the PGD team that you are a candidate for PGD.
  • You will be instructed to call our PGD Nurse Coordinator -- Kristin MacCutcheon, RN -- who will initiate the process for you
  • A Boston IVF scientist will speak with you via phone and will be the initial "point person" that coordiates your care with the appropriate PDG lab. If you have pre-selected a lab, then we will work with that lab, if appropriate.
  • Once you have spoken with a Boston IVF scientist, you will again contact Kristin, our PGD Nurse Coordinator -- who will be your nurse contact throughout the entire cycle. In conjunction with your physician, Kristin will help you to manage many aspects of the PDG cycle -- including treatment scheduling, ordering medication -- as well as general medical instructions and management.
  • You will be contacted via phone and follow-up letter by your financial coordinator outlining the costs associated with the PGD cycle and any fees required for pre-treatment testing, IVF, ICSI (if necessary), embryo biopsy, etc. that are not covered by your insurance.


If you have a single gene disorder or are a carrier of a known chromosomal abnormality:

  • A Boston IVF scientist will coordinate with the PGD lab any pre-treatment testing such as genetic counseling, blood work, or creation of special probes (required for patients with single gene disorders or with known chromosomal translocations).
  • Your financial coordinator will collect fees for pre-treatment testing prior to the actual testing.
  • If pre-treatment testing is required , it must be completed before proceeding further. The PGD lab usually needs 8-12 weeks to develop a probe for a specific gene or chromosomal disorder if they do not already have it in their library of probes.
  • The PGD lab will notify Boston IVF that they have completed pre-treatment  testing and are able to perform PGD for you.
  • A Boston IVF scientist will notify your physician and your PGD Nurse Coordinator that you arenow ready to move forward with a PGD cycle. Your Nurse Coodinator will assist in scheduling your IVF/PGD  cycle in the mpst appropriate time period based on availabilityof the lab and the type of cycle your doctor has ordered. 
  • You will be required to meet with a genetic counselor in advance of your PGD cycle to discuss genetic issues pertaining to the PGD cycle.