I think it's OK to have an honest discussion about the consequences that abortion has on our society. The problem is, it's difficult to build an argument which is logically sound that concludes the effects are anything but a net positive.
Abortion gives women a way to control their own future that they simply didn't have before it was legalized. It's absolutely essential to our modern notions of women's rights. Take it way and it'll be harder for women to have a career without sacrificing a healthy sex life in the process. Women need that option as a "last resort" to live a balanced lifestyle with equal parity to the freedom that men naturally have as granted by our basic physiology.
It's also very important to poor families: if you can't control your reproductive outcomes, it's a lot harder to ever acquire a measure of wealth. There's a skewing of the numbers when it comes to abortion statistics towards low-income women for a reason. These women or couples realize they don't have the means to effectively provide for their children, so they decide not to become parents. Without that choice, we'd have a lot more unwanted children born into this world destined to become disadvantaged youth. Abortion directly aids social mobility.
If South Dakota is so worried about having a larger population of workers, they should be lobbying for the relaxation immigration regulations so that more foreigners can come into the country to fill out our ranks. That population explosion would be a great way to bolster our economy.
Edit: Wroooong place name.