Yea... I read that and the pdf it links to too.
http://www.guttmacher.org/statecenter/spibs/spib_RPHS.pdf
The section you are referring to, "Providers may refuse to participate" refers to states where policies are in place allowing health care providers to refuse health care to the patient (in this case an abortion).
It says 46 states have policies in place allowing providers to refuse to participate in performing the abortion.... hence most state, 92%, allow physicians to refuse and refer...
The states are Alabama, New Hampshire, Vermont, West Virginia, and Washington DC.
I'm guessing those are just states that don't have any policies at all or something... not a policy that says you MUST perform it considering federal law says:
So it would be pretty difficult to force hospitals to force their doctors to do the operation if it's against their beliefs.
Edit: I'm about to fall asleep in my chair. In case it turns out I totally misread everything, I apologize in advance. I'll re-read it in the morning.