There are technically two applicable laws, Health & Safety Code 166.049
, which are both part of the Texas Advance Directives Act, Health & Safety Code 166.001 et seq.
Here is the history of these two sections:
SB 148, 65th Regular Session (1977)
added Vernon's Civil Statutes Art. 4950h, the Natural Death Act, including the "Directive to Physicians" form that contained the phrase, "If I have been diagnosed as pregnant and that diagnosis is known to my physician, this directive shall have no force or effect during the course of my pregnancy." The "Directive to Physicians" form is now in Health & Safety Code 166.033, where it includes the statement, "I understand that under the Texas law this directive has no effect if I have been diagnosed as pregnant."
HB 403, 69th Regular Session (1985)
amended the Natural Death Act to add, among other amendments, Vernon's Civil Statutes Art. 4950h, section 4E: "Life-sustaining procedures may not be withheld or withdrawn under this Act from a patient who is pregnant." That particular provision was not present in the introduced bill but was added during the House committee process. The language is currently in Health & Safety Code 166.049, where it states, "A person may not withdraw or withhold life-sustaining treatment under this subchapter from a pregnant patient."
In 1989, a non-substantive revision bill
moved these sections from the Civil Statutes to the Health & Safety Code. A subsequent bill, SB 1260, 76th Regular Session (1999),
condensed various advance directive and life support-related statutes, including the Natural Death Act, into Health & Safety Code Chapter 166.