In this chapter:
(1) "Abortion" has the meaning assigned by Section 245.002.
(2) "Physician" means an individual licensed to practice medicine in this state.
(3) "Viable" means the stage of fetal development when, in the medical judgment of the attending physician based on the particular facts of the case, an unborn child possesses the capacity to live outside its mother's womb after its premature birth from any cause. The term does not include a fetus whose biparietal diameter is less than 60 millimeters.