More bad news about pre-implantation genetic testing

More reasons to be leery of pre-implantation genetic testing, from CNN:

An older woman's slim chances of getting pregnant could be made worse if embryos are screened for defects before being implanted into the womb, doctors said Wednesday.

Pregnancy and live birth rates were substantially lower among women whose embryos were screened compared with those whose were not, according to a study presented Wednesday at a Lyon, France, meeting of the European Society of Human Reproduction and Embryology. . . .

In the study, also published Wednesday in the New England Journal of Medicine, Mastenbroek and colleagues were trying to determine the value of pre-genetic screening, a process that involves taking a single cell from a developing embryo to look for chromosomal defects that could lead to problems such as Down's syndrome. Doctors have generally thought selecting the most promising embryos will give older women a better chance of getting pregnant.

But some experts have expressed concern that fertility centers promote the genetic tests because they generate profit -- with a single test costing up to $5,000.