Adopting a healthy baby

I saw a comment on facebook today about how healthy babies are adopted less and less these days. The poster said that with the prevalence of abortion and drug use, few babies that are actually healthy are being placed for adoption. To me, this implied that women who live a healthy lifestyle and care for themselves and the child during pregnancy are unlikely to place. It got me wondering if this is actually true, or just coming from this persons' personal experience. I looked online but couldn't find any statistics over whether the numbers of children with special needs vs children without had risen or dropped, but couldn't find anything. Does anyone know where I could find some numbers or have any experience with this?