In the third episode of the Prenatal Genetics series, Dr. Goldwaser and Dr. Fox discuss carrier screening. Carrier screening involves checking two potential parents’ DNA to see whether they have a genetic condition that could be passed on to a fetus, and is usually performed before a pregnancy. Dr. Goldwaser explains that most people are carriers for something, and why in most cases, this isn’t a cause for concern. They also discuss why parents may pursue genetic carrier screening and what to do if they are both carriers for a mutation.