Well, since I am a social worker with physically and developmentally disabled adults, of course I advocate for the individual's human rights every time. If there is a disabled person who is having babies and cannot care for them, the breakdown lies in our system, not with the person with the disability.
I have been doing this so long, I have worked in the hospitals where women were given hysterectomies routinely, because they (administration) couldn't control the sexual activities of a 1,000 plus resident co-ed population. I have seen the births of babies to profoundly retarded females who were sexually victimized by staff. The babies taken away, and even a profoundly retarded woman will wake screaming in the night for her 'baby'. "they took my baby"
I have provided counseling and education to sexually active men and women who may well have lacked enough ability to raise a child, thats why education was so important. I have seen the love and affection showered upon a very normal child by her both mentally retarded parents, who received adequate support and assistance in raising their child.
And of course, there are the very "normal" parents who through, no necessarily fault of their own, gave birth to these very disabled people.
Its a very hotly debated issue in my career field, and not an easy one in which to defend one's position. I do, only because I think I have seen the situation from every possible point, and my vote always goes to the human beings right to choose.