Parents should be able to genetically screen fetuses for genetic diseases. They may not decide to terminate the pregnancy if they learn that their child has a severe disease. It will, however, help them to prefer for possible complications they may face. Additionally, some genetic diseases are fatal before or immediately at birth, so this would help them to prepare for that.
Parents not only should be allowed to screen fetuses for heritable diseases, it should be required. Parents need to know if their child will be born with a genetic disease so they can decide how to care for such a child, or if they need to terminate for the sake of the child and themselves.
Of course parents should be allowed to genetically screen fetuses for heritable diseases. What is the alternative, waiting until the baby is born and it's too late? Then someone has been brought into the world who may suffer a lot more than would've been necessary had they been able to do something in the womb while the baby was still being formed. As a last resort, the parents may want to abort the pregnancy if the child will not have any kind of good quality of life at all due to a severe disease.
I definitely think parents to be should screen their baby for genetic diseases. We should know what's going on ahead of time to be able to treat when the baby is born. It would be very helpful for the doctors of the mother and the baby too. We should not screen for some things, but hereditary diseases we should.
The main argument against genetic screening does not claim that it is bad. It only claims that it could lead to other bad things. We should not be able to choose our children's eye color or personality traits. We should not be able to screen for homosexuality. Yet when it comes to disease prevention, why would we not do everything we can do to prepare for or prevent genetic disease?
Genetic screening might help the parents to prepare for the child but what if they find out that the baby has a disease that might effect the life of the parents a lot and the mother ends up aborting the baby. I think that knowing if it has a disease or not when the baby is actually born is much better because you should love the child anyways.