The baby, a plump little being over half an inch long, with short arms and legs, floats in her amniotic sac, well moored by the umbilical cord. Though she weighs only 1/30 of an ounce, she has all the internal organs of an adult in various stages of development.
The baby's heart has been beating for a few weeks, the sex can be determined and brain waves can be measured.
"Within the sac was a tiny human male swimming extremely vigorously in the amniotic fluid. This tiny human was perfectly developed with long tapering fingers, feet and toes. The baby was extremely alive and swam about the sac approximately one time per second."
Paul E. Rockwell,M.D., describing the baby whose photograph is shown at left
Looks sentient to me. :-}