Most pre-natal vitamins include folic acid because it protects against defects in the formation of the neural tube, the precursor to the central nervous system.
Very early on in fetal development, the ectoderm which is the outer layer of the fertilized egg starts to develop a bit of a ridge that eventually becomes the neural tube.
It seemed that due to insufficient folate, Kim Robbins was born with a hemangioma on his back which turned out to be a neural tube defect — effectively a hole in his spinal column.
We looked at how the brain develops from an unassuming neural tube into three primary vesicles, and then five secondary vesicles, and finally into our complex set of four adult structures and their basic functions.