I'm not sure I see this happening to any great degree. We have had the ability to know the sex of babies in advance for decades, and there are still many parents who prefer to leave it as a surprise. If there are still so many people who don't even want to know the gender of their baby before it is born, how many are going to want to make any kind of changes to it.

Also, there are still a great many people who are very suspicious of any new medical technology and would not want to take any risks when it comes to a child.