In the United States (via countless court and medical opinions) electrical activity in the brain is considered the irrefutable sign of life, or lack thereof.

General Electric, Seamans and other medical instrument companies have prototypes of systems that can detect electrical activity in the brains of 16 week old fetuses. These systems will become available within the next 5 years. What will become of the question of if a fetus is life or not when this happens?

I'm not really Maynard's Girl, I am a 44yo PhD Electrical Engineer that works for one of these companies.