"Black girls and women who become pregnant and know they do not have a stable home in which to raise a child seek an abortion."
Pregnancy is easily avoided as there is only one way for it to occur - sex. Black girls / women are not forced to have a child because the majority of them enter into the situation willingly (barring rape). Are you seriously arguing that girls and women are too stupid to understand this simple reality?
Abortion is merely a method of "excusing" bad behavior and poor choices by placing the cost on the unborn child and society. Removing the natural consequences of sex tends to encourage more sex - which has been an admitted argument of feminists for several decades.