WASHINGTON — The path to parenthood can be emotionally exhausting for couples struggling with infertility, but an increasingly popular screening tool can help ease some stress and uncertainty along the way.
It’s called preimplantation genetic testing (or PGT), and simply put, it helps doctors learn more about an embryo’s genetic makeup before it’s transferred to the woman’s uterus. The goal is to select and transfer a healthy embryo with normal chromosomes, so that it can develop into a healthy baby.
PGT is useful for couples who have experienced a miscarriage (or many), since it decreases the chance of a nonviable pregnancy. (Most unsuccessful IVF treatments are a result of transferring a genetically abnormal embryo.) And by no longer having to guess which embryo is the healthy one, PGT cuts down on a patient’s chance of conceiving multiples, since only one embryo is almost always transferred.
So how does PGT work, exactly? A few cells are removed from the outer layer of the embryo — this is called an embryo biopsy. The biopsied material is sent to a specialized genetic laboratory and the DNA is examined. For PGT, the embryo’s chromosomes are counted (46 is the magic number), and then the embryo is determined to be normal or, if more or fewer chromosomes are present, abnormal.
Additional testing on the biopsied material (preimplantation genetic diagnosis, or PGD) can help parents who are carriers of genetic disorders identify single gene mutations in an embryo, and thus move forward with an embryo that will have the healthiest outcome.
Dominion Fertility, which has locations in D.C, Maryland and Virginia, utilizes PGT on nearly all of its IVF patients. In the long run, the test, which is 99 percent accurate, saves patients money because it cuts down on the number of cycles used. Plus, it means a higher pregnancy rate.
In January 2019, 41 out of 49 patients treated with IVF/PGT at Dominion Fertility had positive pregnancy tests. (Dominion Fertility generally sees a 50 percent live birthrate per transfer of a single PGT normal embryo in its simulated IVF program, across all age groups.)
PGT used to cost thousands, and still does at many clinics. However, at Dominion Fertility, PGT is $150 per embryo, plus a biopsy fee, which makes the screening test more accessible to patients hoping to become parents.