It appears that the consensus in biology is that some microorganisms make decisions (e.g., Bacteria Are More Capable of Complex Decision-Making Than Thought, by anon (University of Tennessee at Knoxville, 1-19-10), https://www.sciencedaily.com/releases/2010/01/100114143310.htm (as accessed 10-8-17) ("[The bacterium] Azospirillum brasilense . . . [can] detect changes in its environments and as a result . . . make complex decisions regarding where to move.")).
I interpret this as meaning that, given a specific set of environmental conditions that doesn't force the microorganism into only one course of (in)action, they might act in any of two or more ways (including inaction) with which way being not by accident, randomness, or next-in-list (next-in-list or -rotation being, e.g., for two ways A and B, always acting in the order ABABABAB . . .), thus by choice (e.g., choosing A or choosing B).
A fetus, of course, is far more complex than a microorganism and is in a direct line of development from at least some microorganisms. Is it fair to assume or, even better, has it been scientifically established that some fetuses, perhaps only those past a certain stage of development but before birth, make choices?