Since the first successful in vitro fertilization pregnancy and live birth in 1978, nearly half a million babies have been born using IVF in the United States. Assisted reproductive technology has made it possible for more people to become parents, but it's not accessible to everyone. Reproductive endocrinologist Amanda Adeleye explains the science behind IVF, the barriers to accessing it and her concerns about fertility treatment in a world without the legal protections of Roe v. Wade.