Columbia subject headings:
Abortion--Law and legislation--United States--Congresses.
Abortion--United States--Congresses.
Unborn children (Law)--United States--Congresses.
Harvard subject headings:
Abortion--Law and legislation--United States--Congresses.
Abortion--United States--Congresses.
Fetus--Legal status, laws, etc.--United States--Congresses.
Unborn children (Law)--United States--Congresses.
Princeton subject headings:
Abortion--Law and legislation--United States--Congresses.
Abortion--United States--Congresses.
Unborn children (Law)--United States--Congresses.