It's good to know if your baby will have a genetic disease. But it's not good to discriminate against ill or disabled babies. Solution, a woman getting genetic screening should sign away her right to an abortion. Not in every case. If it's necessary to save her life or protect her health then it should be allowed. If the baby will have a condition like Tay Sach's which means an early horrible death then it should be allowed. For Down's Syndrome then it should not be allowed.
Whether it is to allay the fears of a prospective mom and dad or to give them the ability to make a reasoned and aware decision either to terminate the pregnancy or to have things ready for the time after birth, genetic screening of fetuses is usually something positive and outweighs anything negative.
The genetic screening of fetuses allows for people to begin treatment or genetic modifications on their child before they are even born, likely eliminating many potential diseases the child is at risk for. I do not see any downside to this, at all, whatsoever. A huge leap in medicine actually.
Genetic screening of fetuses tends to have negative consequences for the fetus. As an example, most fetuses with Down Syndrome are aborted now, rather than being carried to term. This keeps many children from being able to experience life and add to the world. Even though it may help the parents if they want to have a healthy child, it still comes at a great cost.
I do not believe the pros of genetic screenings of fetuses outweigh the cons. We don't have a lot of answers for genetic problems, so finding problems in this area only leaves a person with a very difficult choice. I think it is better to leave things as they are. We shouldn't need to perform such tests until we can treat and cure these problems.