Physician who in 1983 became the first to extract fetal blood from the umbilical cord and to use it for diagnosing disease in the fetus. Daffos's technique, along with that of amniocentesis, uses samples of fetal cells to help determine the current and future fetal health. In addition, by withdrawing a sample of blood, Daffos's technique allows additional testing, for example, for enzyme activity, organ function, and so forth, making it in some respects a more sensitive test than amniocentesis.