The Missouri House has approved legislation allowing health care providers to refuse to participate in some tasks that violate their religious or ethical beliefs.
Wednesday's 117-37 vote sends the bill back to the Senate to consider changes made by the House.
The measure prohibits punishment of doctors, nurses and other health care workers who refuse to participate in contraception, abortions, embryonic stem cell research and certain other procedures or research.
The bill also says pharmacies cannot be required to supply particular medications or devices, and protects employers and health plan providers from being forced to provide coverage for abortion, contraception or sterilization.
Supporters say the measure protects religious freedoms. Opponents argue it would restrict access to health care.