New procedure can prevent genetic disease before pregnancy

Amazing IVF Technology

A new procedure called Preimplantation Genetic Diagnosis (PGD) can now screen embryos for aneuploidy (a condition indicating chromosomal defects) before they are transferred into the uterus during an IVF procedure. PGD can be used for couples experiencing fertility problems, as well as for couples of normal fertility that have been identified at high-risk for passing on a genetic disease. PGD offers a new opportunity to prevent genetic disease from being passed from carrier parents to their children.

According to the March of Dimes, chromosomal and/or genetic anomalies are either solely (13%) or partially (up to 20%) to blame for up to one-third of the 150,000 babies born with a birth defect each year. What's more, recent research confirms that chromosomal and genetic defects are on the rise, linked in part to such factors as advanced maternal and paternal age, family history, environmental toxins, infertility treatments and other unknown causes.

"PGD is a huge development in reproductive medicine," says Mark Leondires, lead reproductive endocrinologist with The Center for Advanced Reproductive Medicine in Norwalk, Connecticut, and one of a few select reproductive specialist in the country doing PGD screening. "We finally have something to offer couples facing the heart-wrenching decision of wanting to have a baby on their own but at the same time being high risk for passing on a genetic defect. PGD offers the potential to significantly improve both the outcome of the pregnancy and the baby's chances for a normal, healthy life. It is very gratifying to be able to offer this kind of hope to patients struggling with questions of risks and fertility," adds Dr Leondires.

The PGD process begins with the steps taken during preparation for a normal IVF cycle. The eggs and sperm are joined in the laboratory, and once the embryos reach the 7-10 cell stage, a cell is taken from each for analysis. Those that are determined to be chromosomally abnormal are not transferred during the final stage of IVF. "When we can ensure the chromosomal viability of all of the embryos we're implanting we can significantly reduce the possibility of genetic disease," says Dr Leondires.

Other benefits
In addition PGD can provide other benefits during high-risk pregnancy. Since a vast percentage of first-trimester miscarriages occur due to chromosomal abnormality, PGD can help also reduce the risk of miscarriage.

"Preimplantation Genetic Diagnosis can be used to screen for dozens of genetically-transmitted diseases, including nearly all defects with a high risk of transmission (25%-50% or higher) and those that carry significant mortality and morbidity rates," says Dr Leondires. "These include cystic fibrosis, Tay Sachs disease, hemophilia, Fragile X syndrome, and rarer conditions such as Barth's syndrome and Rett's syndrome."