CONCLUSION

PGD is an incredible scientific breakthrough. The first ever baby born by PGD was in 1990, that is just over 20 years ago, and now any couple is able to screen their children for disorders before pregnancy even begins (as long as they can afford it.) The more research that is conducted into genes, then the more traits PGD will be able to select for or against. However just be cause we can, doesn't mean we should. I don't think it's right to take PGD beyond genetic disorders. 

I'm a firm advocate for PGD being used to select against embryos that show up with disorders because if it is going to affect the quality of a child's life and you have another alternative, you should be able to take that alternative. Parents want what's best for their kids and a life that's made incredibly frustrating and difficult by a genetic disorder is not what's best for them.  

However, choosing things that do not affect quality of life such as gender (in first world countries anyway) and physical appearance cannot be justified to me. I simply think it is going to cause a heck of a lot more harm to society than good, in the long run. Humans always want to push the limits of science further and further, but this is one area I think we all need to leave well alone.