Pre-pregnancy genetic screening

Genetic testing for inherited genetic conditions is an important component of preconception planning, to assist in assessing the risk of genetic disease in a child, as well as anticipating the management of a woman’s reproductive care. Traditional methods of carrier screening have focused on pan ethnic screening for conditions including cystic fibrosis and spinal muscular atrophy, whereas other conditions, including hemoglobinopathies (such as Thalassemia) and Tay-Sachs, are screened according to a race- or ethnicity-based approach.

However, there are two factors that have changed the method of screening. One is the fact that today many people in the reproductive age group and milti-0ethnic and many may not even know their ethnic heritage making it inaccurate to screen for genetic conditions based on ethnicity. The second is the development of technology to screen for hundreds of common genetic diseases relatively inexpensively using a blood sample or cheek swab.

The result is the recommendation to do universal screening, screen everyone for all the important diseases. There are a number of companies that offer this screening with many different panels encompassing different diseases. Today sperm and egg donors are screened for the most serious conditions.

Since these diseases are usually recessive, it’s necessary to only screen one member of a couple because if that person screens negative, their offspring will be very unlikely to have one of the genetic diseases screened for unless they have a gene not included in the tests. If a member of the couple does carry a mutation, the partner is screed to be sue they do not both carry the same disease thus creating a risk for the offspring.

If both members of a couple screen positive they have the option of having IVF with preimplantation genetic diagnosis (PGD) to assure the transfer of unaffected and hopefully non-carrier embryos. For more information check out our page on PGD.