Recently scientists have developed an extended testing for genetic diseases called pre-implantation genetic haplotying (PGH). PGH uses an embryo from the in vitro fertilization (IVF) process and removes a single cell allowing them to test for more than 6,000 genetic diseases. While this may sound a lot like it's predecessor, pre-implantation genetic diagnosis (PGD), PGH has the ability to not only for many more diseases, but it can also test for diseases even if the specific genetic mutation is not known currently.
This allows the use of more of the embryos. For example, using PGD, if the mother is a carrier for a disease that effects only boys, no male embryos would be used at all. Using PGH, only the effected male embryos will be discarded.
Currently PGH has been used on seven women, five of whom are pregnant and past the first trimester. Each was a carrier of a known disorder like cystic fibrosis.